If there are wrinkles unfortunately there is not much you can do besides open the sail up and leave it in the sun for a while (stretched). The wrinkles I don't think are hurting you. However if you have cracks and splits in the mylar (the clear part of the sail), you need to address these right away. The best way to repair the cracks is to clean the sail well around the effected area, then put clear 3M packaging tape over both sides covering the area around the crack. Most of my kayak sails end up half mylar and half 3M packaging tape after a while ( we sail a lot). Only use good quality 3M packaging tape, not the off brand stuff. Of course you can go buy sail repair tape for ten times the cost if you like (it's basically the same stuff).
One thing that will help you in the future is never let the sail flap like a flag back and forth violently, it will literally destroy the sail in a minute or two of flapping. Always try to keep tension on the sail or furl it up when not using. Of course a little flapping won't hurt it too much, it's the violent flapping you need to guard against.
Hope this helps