Use a Cake Tester
We use cake testers all of the time at Baking Mad but you could use a tooth pick or a kebab skewer if you don't have a purpose made one. Simply pop the tester in to the middle of cake. It should come out clean if the cake is baked. If however, it comes out covered in batter (no matter how little), pop the cake back in the oven for a couple of minutes and keep checking with the tester until it's done.