Optional: Use the pointy end of the spudger to remove some of the gunk/buildup within the key fob.

Insert the control module back into the key fob, making sure all the buttons line up with the holes.

Reattach the two halves of the key fob on the side opposite of the key first, then continue until the entire fob is back together in its original state.

Don't forget to put back the Phillips screw!