[Pokefan6933]

Ok so i've been playing pokemon for quite some time and i realized when i was alot younger i bought a gameshark but didnt no how to use it...and i still dont no now haha. So i have the V.3.1 gameshark and a pokemon yellow. I turn the game on and it says gameshark blah blah blah start game blah blah blah then in game i press teh button at the bottom and it brings me to a gameshark menu...so what do i do now for cool cheats and stuff? and theres also a switch next to the button that goes left and right what does that do? PLEASE REPLY AND HELP ME!