wow you posted this a while ago but I'll respond in the best way I can
I'm in a gap year right now and retaking all of my A2 modules as a private student. obviously results day is in august so I've not got them yet..perhaps it would have been better for me to respond to this after results day lol. Anyway, I'm coping pretty well, I've got a lot of material from last year and ordered some revision books online to help me further, not to mention TSR is very helpful too!
You don't have to say in your personal statement that you're retaking - I didn't. but you do have to declare it on your application, so I had to write my old A2 grades and then put the subjects I'm retaking now and tick the 'pending' option and the centre/school I'm resitting them at. Everything else is exactly the same
hope this was somewhat helpful