Saved up my annual leave, read the AP, did some sums, then PVR'd.
After adding up all the public holidays, resettlement time, terminal leave etc, my PVR application went in and I was paid until 8 Aug. I even made sure that I turned up for work between Christmas and New Year (even though I sat around doing nothing) - all to maximise leave time carry-over. Also, don't forget that the Apr-May period is another source of extra free paid days, due to all the bank holidays etc!
Last day in uniform was 10 Apr; my 'approval to conduct part-time, off-duty civilian employment' was already valid until 3 Sep. So, as I had plenty of 'off-duty' time from 11 Apr - 7 Jul (after which I could, if I'd wanted, take full-time employment), it was a nice little earner!
Don't forget to include the day for your release medical and the day for the resettlement brief in your calculations - and it might be worth waiting until just after the new pay scales come in before PVR-ing
Research your entitlement, keep some leave to carry over into the next leave year, then get a year planner and a cup of coffee and count backwards from the release date to establish the happy day when you can throw your gas mask at the stores basher!