Congrats boyo! Welcome to the addiction.
Now that you have a nice new saw that is accurate and true, go to Homie Despot and buy a sheet of 1/2" or 3/4" birch plywood -not the cheap shit. It will cost you about $50 but you want something that does not have a lot of imperfections on the face. Then take it home and make some perfectly square boxes for your shop. Store nails in one, screws in another, your Playboy collection from high school in another; I don't care. Those boxes are your jig for making perfect 90 degree corners. It is MUCH easier to clamp a part to the side of a plywood box using a plain old F-clamp than using stupid corner clamps. Plus, F-clamps are much stronger.
You da mang!