skin up

1. To scrape off the outer layer of skin (from something). A noun or pronoun can be used between "skin" and "up." I skinned up the palms of my hands when I fell off my bike. He skinned his elbow up when it scraped against the brick wall.

2. To hand roll a cigarette, especially one filled with cannabis. Hey man, you want to come by and skin up a little later? He always goes to his car on his lunch breaks to skin up.

skin up

1. To bruise, cut, or injure the skin or surface of something: He fell off his skateboard and skinned up his knee. She slipped on the sidewalk and skinned her arm up.

2. To roll a cigarette: I pulled out a pouch of tobacco and skinned up.