Make sure you get a 2:1. Only a couple of places ask for a first, but a 2:1 will keep most places open, if you get less you'll be really limited.
Get work experience. Warwick currently ask for 70 hours in the past 2 years when you apply, so don't necessarily get it all early, or if you do acknowledge that you might need more.
It's far into the future, but don't underestimate the value of entrance tests. If it's possible for you and you want to apply to UKCAT unis, maybe sit the UKCAT the summer before you need it to apply as practice is good.
Try and save some money. At the moment you need £3465 in Y1 towards fees, but this may change in subsequent years. Also, it never hurts to have some savings for the long terms in graduate medicine!