The best way to remove oil from a cement garage floor is to use cat litter. That’s right, simple cat litter will absorb the oil right from the cement flooring. The reason cat litter is probably a great option, aside from the fact that it is one of the least expensive materials to buy, is that it is made to be extraordinarily absorptive. One thing to remember, though, is that you should promptly remove the oil when it is still wet. If it gas dried, try putting a little more oil on top to mix with the dried oil, and then apply the cat litter.