I would like to install ceramic tiles in my basement. The floor is concrete. What do I have to do?

Clean the area to be tiled very well. Use water and a mop. After it dries you can start tiling. Use a dry-set or latex-portland cement mortar (aka-thinset).
If there are any expansion cracks cut into the concrete do not span these cracks. You will have to have a tile joint match the concrete joint. This does not get grouted but filled in with color match caulking so it can move w/ the concrete.