Whenever I get grease on my stove top I always try to wipe it down with some dawn dish soap and water after cooking and spilling the grease.
This keeps it clean so it's easier to clean off.
But even then dawn dish soap and some water on a sponge will usually clean the grease right off the stove top but if you have a lot more grease that is harder to get up then you might want to use some oven cleaner and spray it on the stove top and let it sit for a few minutes.
Then wipe it down with a sponge, paper towel or wash cloth and use the soap and water to clean it off.
Purple Power degreaser is also a wonderful product that doesn't put out harsh fumes and it's safer to breathe in than the oven cleaner is.
Usually vinegar can take off some grease as well but you want to use undiluted vinegar for the best results.