How do I properly shuffle a Rubik's Cube?

I have Cube that I'm learning to solve, but what is best way to scramble a solved cube to make it sufficiently random enough to be "challenging"? Also, a related question (sorry 2 in 1), what state of cube is the FURTHEST possible moves from a solution? And how do I obtain that state in my cube?... show more I have Cube that I'm learning to solve, but what is best way to scramble a solved cube to make it sufficiently random enough to be "challenging"?

Also, a related question (sorry 2 in 1), what state of cube is the FURTHEST possible moves from a solution? And how do I obtain that state in my cube? ;)

Thanks!

(p.s. for cubists, I am currently at 4m15s for solving time)
76 answers 76