If you have a trailer winch strap which is broken, then you may need to repair it before you use the trailer winch again. Rather than replacing the trailer winch strap, you could perform a quick repair which will help you to hold the strap in place temporarily until you can perform a long-term repair or replacement.
Step 1 - Remove the Strap
Take off the strap of the trailer winch. You may be able to do this by uncliping the sides, but some models may require you to remove a bolt or screw which is holding it onto the side of the trailer. Pull this off, and then examine the tear. If it is a large tear, then you should dispose of the strap and replace it with another. Smaller tears can be sewn up.
Step 2 - Sew the Tear
Take out a sewing kit, and find some heavy-duty thread. Thread the needle, and then make a few quick stitches to hold the two sides of the tear together. You should then sew some closer stitches using smaller thread, securing both sides of the tear tightly together.