Flat coat mid grey or beige (depending on colour of granite) then dry brush stipple with a stiff brush all over the base coat in an even manner. repeat this with the other colours you want to be in your countertop, until it resembles what you are after. Use a quality sealer( flat or satin ) to complete the job, and always use Cutting boards etc...............
You can find pretty convincing laminate versions of most stone.
Hi Elaine, I've seen this done and it looks great. https://www.hometalk.com/11441901/easy-faux-granite-counter-top
If you have a ceramic tile counter the best you can do is make it look like granite tile. Tile shape and grout will show thru