how do i make non animated icons les than 40k?

i just got ps7 recently, and know how to use brushes, gradients, etc. But any non-animated icon i make is way over 40k. I know you'll say to reduce layers, but just adding ONE gradient or ONE color fill-or even dupicating the layer puts it near the 100's. I even tried following an icon tutorial, using their exact steps, but my icon was still over 100k. any idea what im doing wrong?