The names of these moves are somewhat arbitrary, and different people call the same move by different names.
The basic skip up is this. On counts 1 and 2, they rock step. On counts 3 and 4, they kick left and step left. On counts 5 and 6, they kick right and step right. (The kick step left and kick step right may be repeated any number of times.) On counts 7 and 8, they exit.
Skip Ups in Closed: End with tuck turn or big kick at end. Both directions.
Skip Ups in Open:
Change Direction: Instead of repeating kicks, the next kick left should push on hip, and on step, they turn and rock step. This switches the feet orientation.
Free Spin: Instead of changing direction, they can do a free spin and come back together in the same position.
Tempo: Fast or slow.
Feet: Step, kick step, kick ball changes.
Arms: The arms usually hold onto the partner, so there are few variations (tied up).
Direction: Forward and backward.
Footwork: They can step, step; kick step, kick step; or other.
Skip Up: walking steps (forward, backwards, skipping, skating) (all directions) Pull the follow's hip right next to the lead's hip.