So this is going to be based around my own experience; if you know what degree you're going for, professional degrees like law and medicine you can likely skip this 

Myself 

So first I'll talk about my own experience. (You can skip this if you want) While I'm typing this, I still have reservations about my course because I still have no idea what I'm going to do. But remember, this is normal. My classmates are still continuously changing their subject choices, and again, this is normal. Unlike the US where you start off with general study, the UK requires you to specialise in undergraduate, meaning you have to choose one specific course for application, and because of the personal statement, your choices are likely to be similar.

Here is my tentative list of course choices:
1. Cambridge (HSPS - Sociology, Anthropology and International Relations) [A*AA]
2. LSE (International Relations) [AAA/AAB]
3. KCL (War Studies) [AAA]
4. UCL (International Social and Political Studies) [A*AA]
5. SOAS (Internatioal Relations and Social Anthropology) [AAA]

Notice how they all have one common principle - International Relations? Again, it's important to choose courses that are similar so you can hone in your personal statement.

So how I decided on this course took a lot of suffering, deliberating, struggling and thinking. I first decided to do War Studies because I was interested in military history (that was three years ago, I think). I've been interested in humanities for a long long time, so I was already dead set on doing it in college. I initially wanted to go for History, before my mom told me to do one that could be more careers-based. I really wanted to go to Cambridge, so I narrowed down my choices starting from that, but if you're applying to other schools you can choose whatever you want. 

Anyways, the careers-based history-related subject available in Cambridge is the HSPS one, so I decided to go for that. I basically just chose my subjects from the top schools in the country (again, family pressure). Notice that most of my choices are multi-disciplinary courses. Again, this is entirely up to you. I wanted to go for a multi-disciplinary one because 1) I couldn't choose between all humaities initially, and 2) I know I'll get bored if I stuck to just one course. 

(Fyi if anyone's remotely interested I wanted to do International Relations and English Literature but none of the colleges that offer that was high-ranking enough so screw me :)

So yes, that's basically how I chose my subjects! No logic whatsoever, so you'll probably be better off with the tips below. 

General Tips 

This is a list of tips that I guarantee significantly narrows down your choice-making process. I'll be going through your consideration process, before talking about what can narrow it down.

Choosing your course

1. Choose a course you like, or have interest in, or can at least tolerate. 
- It is extremely important that you choose a course you like. Remember, you'll be spending three to four years (six for a med degree) living and breathing this degree through, and you'll be suffering a lot if you don't choose something you even remotely like. While you can change your degree after you went into the school, it's usually not encouraged and it's harder to do so. 
- If you're unsure whether you actually have interest in what you choose, or believe you know too little to be able to choose it, do some more reading around the subject! Or start an academic project, or do an online course, it's entirely up to you. Just be sure that you know what you're in for, because otherwise it'll be extremely difficult to wriggle out of it. 
- Also, if you choose something you like, it's also easier for you to score better in it. 

2. Choose a course that will aid your career. 
- If you've already decided on your dream career, then choose a degree that will help you get there. Professional degrees like medicine and law is a must, but if you're heading for a political career better choose something related to that so you can get into it easier. 
- That said, there's really no limitations, as long as you aren't a humanities major applying for a biomed tech job. (And even then, there's this thing called a Masters) I often hear people saying you don't get a job just studying humanities. That's not true. As long as you're good at your subject, you can get a decent job anywhere. That's why you should pick a course that you can, at bottom line, tolerate. 

Choosing your school

3. Choose your preferred school.
- Don't forget that your school also counts into the choice. Again, since you'll be living and breathing and sleeping and basically spending all of your wakening hours there, choose a school where you like the campus and the city. 
- Pick a school whose surroundings you like! It's that simple 

4. Opportunities
- If you don't have a preferred campus, look at the opportunities it can offer. There are strategic places you can go for for certain benefits. For example, if your school has been doing a lot of med investigation, and you're interested in that, go there. In my case, because SOAS is the best research institute for Asian and Pacific related topics, and I like that, I'm applying there even though it isn't ranked high. 
- The city also matters too. For example, in London I'll be able to find more international-related opportunities even though I have a personal grudge against London. So pick and choose wisely. 

5. Student Satisfaction
- Each university has a scale called 'student satisfaction'. It's basically how satisifed students are studying there, and it helps you make a judgement. However, because this can be very finicky, it's best to go on student forums and Youtube for further information. 

What restricts my choices? 
1. Your career
- If you don't have a set career, great! Choose whatever you want. However, if you're going for a professional degree, there are limitations on what you can choose.

2. Your grades
- As I mentioned in the page before, your school gives you predicted grades before you apply to anything. This means that certain courses, especially ones at the higher ranking universities or the most demanded ones, would be out of your reach if your grades doesn't match up. If you only got a AAB in your predicted grades, obviously Cambridge, with its normal offer at AAA*, will be out of your reach. 

3. Money
- Sad truth, but unfortunately true. Check the fees before you apply, because it's so expensive for international students. Check if the school has any available financial aid as well. (I can't elaborate on this because I won't be applying for financial aid) 

4. Your PS 
- Ultimately, you need a focus in your PS. And because your PS is going to be sent to five schools for your choices, it needs to appeal to all of them. So you have to pick five similar courses. 

5. Availability of courses
- Unfortunately for me, there are a lot of schools that don't offer my course, because I'm going for a combined honours AND a rare combo. So from the get-go, there are some schools and courses that are already closed off for me. 
- Also remember to check the nature of your college; if you're a humanities student and you want to go to Imperial (which is a traditionally very science/business-based university), it's highly likely you won't find anything suitable for you.

6. Your UCAS app
- It is wise to divide your UCAS app into three categories of choices based on their grades qualifications. It's usually like this: 1 - 2 aspirational, 2 - 3 achievable, and 1 - 2 safe. I'll use a predicted grade range of 3A*s and 1A (which is what I'm aiming for) along with my list of colleges as an example 
- Aspirational means a course you want to get in, or a course that if you pushed yourself really hard, you can get into. Because the highest grade in the A-level scale is already A*, it means a school that you can get into if all your predicted grades are true (because again, you can't apply for a school whose grade qualifications are too high). So for instance, Cambridge's typical offer is 3A*s and 1A. If I could fulfill my predictions, then I could get in. (Just based on grades)
- Achievable means a choice you can get in on a normal day. To put it crudely, it's a course you can get in even if you don't study at your best for A-Levels. So, say my achievable grades are 4As, or 3As and 1B. I'll then be choosing courses with those grade qualifications.
- Safe means a choice you can get in even if you had a bad day during your exams. This is for insurance, so most ambitious students only stick one into their choices. You can see that the courses I'm applying for don't even have a B qualification for them, except for LSE (which is fake anyways, because LSE has the best International Course in the country except maybe Oxbridge). This is because my insurance lies in my own country (which will not be disclosed for personal reasons); I'm planning on applying back to the unis in my country and that is my insurance. For those who're just going to be applying UK, remember to put in at least one safe choice. You need something to fall back on. 

What you shouldn't base your course choices on 
1. Prestige of school
- Don't go to a school just because it ranks high. Go to a school because you actually like it, or because your subject is good in that school. It's a coincidence and family pressure that my preferred choices are all in the top 10 UK unis, so please don't reference my list. Go for something that's achievable for you. And again, even if the school is great, you may not like it.

2. An easy course at a famous school
- Some people do this thing where they pick an easy to enter course at a famous school, like, idk, maths at a law school and get in first, before changing your major just for the prestige of the school. Don't do this. It'll piss off the teachers high time and it's likely that you won't be able to get in if you don't have passion in the first place. 

TBC 

(There might be more, but for now I can only think of these off the top of my head so ask me if you have any questions!)