hmm... it depends if your saddle is ok for you, but that might be something you need to look at in the long term.

any ointment that promotes skin healing will help, I use something that has quite a lot of vitamin A in it.

You might want to put some of that on (or rather a lot of it) before the ride. There are chamois creams out there specifically sold for the purpose, but I just use a lanolin-based wound healing ointment. And I put some fresh stuff on after the shower if I did chafe.