Alternate one-hand form shooting from each block (1 shoots, then 3, then 2, etc.), then move up to a mid-lane position, then to the elbows.

(Variation - use a guide hand)

When Nash comes in the gym he starts real simple, gets his basics, timing and mechanics down, that's why he starts in close to the basket to get proper form, rhythm and his confidence up so that when he steps back he feels really ready to shoot the ball.