You can find plenty of guides through the internet that will show you how, but I highly suggest for you not to do it the first time. If you clip too much of a feather is CAN hurt, but when done right, it doesn't harm them.
Avian vets can clip them for you or some bird breeders can(the person who bred my Quaker clipped his wings before we took him home). After you are shown how in person, then it might be okay for you to do it. I still don't feel comfortable with clipping them myself, though.
I haven't a clue on how much it costs, because I can take my birds to Don(my quaker)'s breeder, and she'll do it for free. I'm sure it can't cost too much, though.