I find using plastic is a huge hassle and is not as affective as using brown paper that you can buy by the roll in the paint department.
Plastic always has the tendency to move, or get torn, or get its “panties in a bunch”, as people walk through the area. It also likes to stick to things once paint gets spilled on it. I have been one of the “things” it stuck to.
The paper is nice and flat and stays that way. I taped the seems up so if anything gets spilled it will not run under the overhang of the other piece. Plus I find the paper is a lot cheaper than the plastic drops.
This was written for a non carpet floor…I haven’t tried this out on carpet yet, so I cannot say it will work on carpet. I think plastic would be better on carpet.