If you have a Facebook account, you've probably seen this video on your timeline, and so have your students. Whoever came up with this is clearly an artist, but you don't need to be one to use cup twisting in the classroom.
The first thing you need is a base element and some complementary ones which can be overlapped such as the body and the hair in the video. You could either draw them straight on a plastic cup or stick printed pictures on it. Since drawing on a curved surface can be quite tricky, I’d rather work with the second method. It’s very easy and you could count on your students to help you – and they will really enjoy it!
Making stickers for a cup twisting activity will require printable label paper (those with one label per page). If you can’t find it, slips of contact paper, transparent tape or multi-purpose glue will do the trick as well. Search online or scan the pictures you want to use in your activity and make sure you resized them so they will fit on the cup surface. Print and cut them out. Remove the protector from the label paper and stick the base picture on a cup. Then put another cup on the top of the first one. Now stick the complementary pictures on it with a reasonable distance from each other in a way they seem to be part of the base picture. You could stick one, twist the upper cup a little and stick another until you've used all the set. If you've printed them on copying paper instead, use slips of contact paper, transparent tape or multi-purpose glue to stick the pictures on the cups following the same steps.
Since cup twisting activities will give your students changing scenarios to talk about, there are a number of ways you could use them in your classroom. Learners could drill target grammar structures, fill in the blanks, ask and answer questions in pairs or even do an interactive listening exercise. Here are some other examples of activities to inspire you. They were developed to young learners, but I'm sure you could adapt the same concept and apply it with teenagers and adults as well. The printable files used to make them are available here and here.