Set yourself up with your sketchbook and pencil across from a peer. Yes, you may need to move to be directly across from them.
You each need to situate yourselves across from one another in such a way that both of your hands are relatively near each other.
I know one will be drawing, but the other one should be in close proximity.
Your task is to draw the hands of the person across from you.
Remember that context may be helpful.
Remember that being done in a very rushed looking manner isn't of primary importance. If you can get some good drawing quantity, cool, but balance quantity with quality.
If you are really focusing you won't be involved in discourse or logging in to listen to music.
Please just be present and focused.
And have fun.