What shower gel or such do you use? Try Sanex or Carex, the antibacterial ones. If you like more smelly stuff then you can use both. I use the sanex all the time then do a quick rinse over with some nice smely stuff.
It may be an idea to ay off the smellies for a while though until you get your skin back in shape. If you liek the smell maybe get some nice body sprays instead, the Body Shop do some lovely fruity ones.
Try exfoliating but nothing to harsh on your bum, the shower gloves you can get are great and can be used in the shower with your antibacterial stuff.
Maybe even try getting some gentle sensitive cleanser to put onto your skin and some oil free mosturiser or lightly dust over with some talc (gentle or medicated, not perfumed) using a large blusher brush if you're going to be doing anything hot and sweaty but make sure you don't clog the skin.
A hot flannel placed on them (or a sauna or team room)open the pores then put some medicated lotion/anticeptic cream or similar or tea tree oil on overnight. if they're really big then pile cream can take the swelling down but watch as it can be very greasy.
Make sure the area gets lots of fresh air too if you can get it somewhere private :) Try not to wear underwear at night, such as a nighty which lets your skin breathe. Wear cotton underwear during the day and breathable ones for sport as skylight recommends.
Check your diet too in case it's not very skin friendly and make sure you drink lots of water.
Hope this helps x