The objective is to clean the carpet as best you can by removing these stains.
bits of carpet
A bristle brush
Bicarbonate of soda
PPE (gloves, maybe googles etc)
We cut up an old carpet to squares, could always get samples from a friendly carpet shop.
We then put some stains on this, we did a muddy boot print, some paint, Tomato sauce and coke. We also to shake it up a bit had some that were wet and some that we had allowed over night to dry in.
We then gave them some different cleaning things, make this relevant and safe. We used Salt for the wet coke, a simple brush that was for the dried muddy boot print, white spirit for the paint and then just other things like sprays and soap and water. Obviously you need to give the big talk at the start about safety with sprays and white spirit around.