How would I go about doing that? I have never done it before.
I presume you are refering to "jumpering pins 30 and 87?"
In the fuse/relay box under the hood is a relay marked "Starter Relay"....it is shown on the decal on the box lid usually.
Make sure you are in Park/Neutral so you do not run yourself over if the engine turns over.
Pull out the Starter Relay....you can quickly swap it over with an identical relay nearby...ie. same part number....just in case the actual relay is faulty.
Now that the Starter Relay is removed, flip it over and you will see the pins are numbered...you are only interested in pins 30 an 87. Make a note of where those pins will go inside the relay socket...sometimes the relay socket has pin numbers marked already.
Now with the relay still removed, carefully insert a piece of wire into pins 30 and 87 in the relay socket... a straightend-out paper clip should do.....the solenoid should engage and turn the engine over.....if not then check fuse 8 (40 A) in the same fuse panel.
If this works, remove the paper clip and turn on the ignition key to the last position before the final "start" position. Now jumper the relay socket points 30 and 87 again.....if you are lucky the engine will fire and run so quickly
pull your wire jumper out or the starter will stay engaged to the now running engine.
If this works then we need to chase the error down with a few more steps but at least you can drive the Jeep.