Write a one-paragraph or one-page scene. To write that scene, play a simple connect-the-dots game with words circled from prior warmups. Go trawling through your notebooks with a pen of a second color, or if you have nothing on hand, do a quick set of minute lists, select words from there, and weave them into a your scene.
Then rewrite the paragraph (or page), starting with the same first few words but allowing the details, imagery, and action drift just a little. Reweave the scene at a slant, so it becomes a slightly different scene.
Repeat as many times as you like. Let each new iteration make space for something new and true to appear in the scene.