I got into one. Here's what worked for me:
1. Write a good personal statement
2. Get some relatively solid references from 6th form teachers.
3. Get teachers to inflate your predicted grades to a point where they're quite uncomfortable with them in order to meet the offer.
4. **** up your exams a bit and miss the offer by ~5 grades.
5. They take you anyway.
RG is not hard, and does not mean anything. If you get a decent statement and actually do well unlike myself, then they're probably gonna take you. I was playing with fire, meself.