I have a newer radio and want to install it, but isnt sure which wires connect, they are different colors

Use a volt-meter or test light to find the positive supply power from your vehicles wires, and the ground wire too. attach those to the new radio's power wires (and attach the new radio's ignition power wire, or switching wire to the positive power wire from your vehicle too). The point will be to get power to the new radio so that you can do a trial by error to find which speakers turn on when you connect them. Just follow the sound! after you have found all the speaker wires. the last thing is to find which wire from your vehicle needs to be attached to the ignition wire on your radio. This wire makes sure your radio is off when your keys are turned off so not to drain the battery. if you cannot find a switching ignition wire, run a wire to a connection in the back of a fuse panel connection (which you can test any connection with your volt meter to see if it shuts off with the key.