Cleaning a wound?

My longhaired cat and her tiny playmate (little stray kitten we've decided to keep) were roughousing for a good deal of yesterday, and although his claws are trimmed, she's got a good-sized chunk of fur missing right next to her ear, and the bald patch is very painful-looking and is causing her obvious pain (I first noticed it because she was being flinchy). The hair above it is trailing into the wound. should I shave around it?

I have a small safety shaver (electric), which she is used to hearing. What is okay and not to painful to clean the wound itself with? (I do not want her to fear me touching her, as she's bonded with me closer than anyone, and it may lead to her being more withdrawn around other humans than she is now. however, I know that it will hurt her more if it becomes infected, so I want to try to keep it as clean as possible).

I would have taken her to the vet's, but it is Sunday, and all of them are closed.

Hopefully some more edcuated folks will come... but Kandies last boo boo the vet sent me to get hydrocrotozone cream... I also get an anti germicidial on hand

I would be reluctant to shave the area because my own cats would kill me if I tried to bring a buzzing thing near them like that. Is the area warm to the touch? Is it scabbed over? You may want to remove the scabs or put a warm compress on the area. You can use a small syringe without the needle (or anything else that will create a small stream of water like a ziploc baggie with the end cut off) to flush the area with lukewarm water or sterile saline solution (usually near the contact supplies at the grocery store). It may cause her some pain, but sometimes it is necessary for the kitty's well-being.

I would not use hydrogen peroxide because it is too abrasive, especially near the eyes. Stick with slightly warm water or saline solution. If it is warm to the touch, she will definitely need a vet as it could be developing into an abscess.

Generally, we do shave around the area in order to keep fur away from the wound. However, clippers may frighten her and because of the location of the wound (near eyes and ears) I don't know if I would shave it by myself. A lot of the time, shaving cats around a painful area is usually a two person job.
We usually use hibitane (among other anti-bacterial soaps safe for cats) which is applied via the use of gauze to clean the area twice a day if the kitty permits it. Again due to the location of the wound, I wouldn't flush the area as you may get fluids in the kitten's eyes or ears. We remove the soap by using wet gauze and then pat it dry with another. Keeping the area dry is extremely important in order to prevent infection.
I would really get your little kitty in to see your vet when they open for any necessary treatments. Does your kitten mind nail trims? If possible, I would try clipping her back nails in order to reduce any further damage she may cause by scratching the area.
Good luck and I hope the wound heals fast.