Is it a pen with a dirt floor? Are you having a problem with odor or just poop build-up?
I have one little house and pen combined that has wheels on one end. That one I just move to a clean area.
For my stationary run/pen, I have a thick layer of sand in it. I can rake the dry poop out of it. Sand in the run/pen is popular with a lot of people here. Most of it has a roof, to keep it drier and keep it from smelling, as we get a lot of rain here. My chickens also live in a coop at night or in bad weather, which has a layer of wood shavings in it.
Sometimes, rain will wash a lot of the poop down through a gravel or sand run, as it breaks down.
For a dirt pen, you could try scooping out the top layer. Digging a little lime in can help with smell, if it's a problem. You have to make sure you don't use the kind of lime that's caustic and can burn skin.
Some people use some type of organic matter in their pens. I've seen people use leaves, straw, wood shavings or hay. For that, they usually shovel it out when it gets too dirty. Although if you have a lot of space, sometimes it just gradually breaks down and disappears.