What EVERYONE should do is have a vague idea of what course(s) they might want to do at uni. The thing I regret most about my choice of a-levels was that it was picked according to a criteria of what I enjoyed most; a better criteria would be which courses will help me do the degree I want to do most. As such, I did not pick maths because I did not enjoy it as much. But come university application, and I found that what I want to do most as a degree (economics and philosophy) is not allowed for me because I do not have maths. I have picked up Maths since then.
Another advice is that stick with 'traditional subjects'. As you might or might not have heard, there is a subject 'black list' that respected universities have, i.e. subjects that are seriously disrespected because they are not academic enough (some myths claim that your application is sent straight to the shredder if that subject is found on your UCAS). This black list includes subject like media, drama, sociology, psychology and unfortunately Eng. Lang and Lit. (because it is considered a 'diluted' version of both subjects). I would definitely advise you to pick English Literature because it is a very respected subject to have!
Last advice is that you should keep a mix between the sciences and the arts. Unis like well rounded off applicants who haven't closed themselves off too early in their lives.
Your ideal choice, in my opinion, would be English Literature, Biology, History and Philosophy.
PLEASE PLEASE PLEASE avoid Psychology and Lit and Lang.
ALSO, contrary to popular belief, the EPQ is not respected as much (by the top unis at least). However, the EPQ is useful to put into your personal statement and as such it creates an interesting discussion point at your interviews - if you do do (haha) one, make sure it is something very academic and very distinct. If you're doing it on TV shows or Football or something, there really isn't a point : the qualification itself is not worth anything (maybe some UCAS points , but the top unis don't care about that).