High, Low, Medium, Slow
Thanks to Kathleen Garber, who helped me solve this skipping mystery. Here's the complete verse:
Turn the rope according to the words:
Wherever the skipper gets mixed up in the ropes during the rhyme, that's how they need to skip the next time they're in. "High" - the skipping rope is a foot off the ground; "Low" - the skipper needs to bend down to skip; "Medium" - normal skipping; "Slow" - slow skipping; "Pepper" - really fast skipping.