i had made an event proposal once,but not sure if it's the same format for diff countries,so i suggest u better browse it thru internet. As for how to make it acceptable,for mine, one of it was i made layout design for it,so ppl who read it will not get bored. But the content of the proposal should be the main point still. In other words,to support the main content,make the outer appearance of ur proposal as xtraordinary n interesting as possible,which makes it looks different with others,so it will stand out more to be noticeable at first. U can make the cake-theme-alike layout,but dont add too much designs,so the proposal will still looks elegant n readable. There's nothing much i could suggest n dont know whether u still need suggestion (bc u posted it 3 days ago) but hope it will be helpful :)

Are event proposal the same for all countries? Hehe.. and is this like for work or school or what? :)

http://www.leoisaac.com/evt/top075.htm