The best times are usually from daylight to around 9:00 - 10:00 AM and then from around 4:00 - 5:00 PM on to dark. If it's colder, then the squirrels will usually wait a little after daylight to come out (to let it warm up). Use the squirrels activity to dictate how long you hunt. I've seen them active all day, so if that's the case, then stay out all day. If it's windy, you might as well stay home. Same thing for a rain, unless it's a light rain and it's warm.
As far as cooking, I think the best way is to just fry them. Get some peanut oil and heat it to about 200 degrees and drop your squirrel in the oil. Roll the pieces in some seasoned flour first though.
If you want a "crust" on the squirrel, take a couple of eggs and mix them up good in a bowl. Roll the squirrel pieces in the egg first and then the flour, and then drop them in your oil. Make sure the oil is up to at least 200 degrees before you put more squirrel in.
The recipe section here has some other ways to cook them. Be sure and try the Squirrel & Noodles.
