Want to flush my tranny fluid this weekend, whats a good aftermarket/recommended tranny fluid?

I use Royal Purple ATF. It works very well. I've seen a noticeable difference over using the stock fluid.

I'm going to try Amsoil this spring...

can anyone tell me how do you flush the tranny, I would like to know.
Thanks
David

Thanks for the tips guys, regarding how to do this. I have a friend who is going to be helping me, because this will be my first time also!