Automatic window in my truck doesn't roll up anymore, how can I fix it without taking it to a shop?

It's a 91 Ford F150. It use to roll up, but not anymore.

Open the door, turn on the ignition, press the up switch.
look at the dome light. Does it dim when you press the switch?
Then you verified the 2 circuits.
Hold the switch and smack the door panel. Did the glass go up?
Then you have time to get a book, some tools, or a mechanic friend to help.
you need a drill, some (steel ) rivets and a riveter. Some drill bits, and a working knowledge of tools and their usage. A 10mm deep socket, an extension and a ratchet.
Now based on your symptoms you need a motor and decide if you need a regulator.

Or you can take it to the ford dealer and price a repair.
If you had electrical issues during the first few steps, the switch, wires and circuit protection may come into play before completing the diagnosis.

First you should make sure there are no blown fuses/tripper circuit breakers in the circuit. Then you need to be sure the switch is good. But seeing as you've probably tried from the passengers side as well we'll assume for now the switch is ok. Just for the heck of it, and because I've seen it happen before, open the drivers side door and pull back the rubber boot that is in between the door and the vehicle. Make sure there are no broken wires. Do the same thing to the passengers side. It's very possible you still have a good motor and you simply have no continuity through the circuit. If you have no breaks in the circuit and the switch checks out OK, THEN its safe to assume its either the regulator or the motor itself.