Starter just clicking after head gasket replacement

I recently replaced the head gasket on a 95 Geo Prizm. Now when I tried to start it, all I get is the starter clicking. I tried tapping the starter silinoid, to no effect. The only electrical that I messed with during the head gasket replacement was to disconnect the battery. Please help!! My girlfriend realllly wants her car back!!!

You need to take the battery terminal off again and clean it. Another step you can take is to make sure the engine will rotate by using a breaker bar and socket on the front of the crank. Sometimes coolant can leak down a cylinder or two and you can get a hydraulic lock. If you can’t turn the engine over then remove the spark plugs to allow the coolant to escape. Leave the battery disconnected while you attempt to turn the engine over manually.

Check to make sure you didn’t forget to re-attach an engine ground wire on or near the head.

Check to make sure the battery has about 12.4V, minimum.

Can you turn the engine by hand with a socket wrench or similar to verify that it isn’t seized up? Was it sitting for a while before the gasket replacement? It may be you have some rust in the cylinders if so. If this is the case, pour some penetrating oil into the spark plug holes and let it sit for a couple days before trying again.