You can use just about any pliers you want to close the cover; however I like to use the mighty crimper tool. You can use whatever is easiest for you. Place the jaws of the mighty crimper, chain nose, or flat nose pliers around the crimp cover and start squeezing gently. Because the crimp covers are small, it can be tricky to grip them with the mighty crimper at first, so you might try closing the cover part way with flat or chain nose pliers and then switching to the mighty crimper. While you are doing this step you should also watch to make sure that the crimp cover is not closing lopsidedly. If it is, you can correct it by moving your tool to squeeze it a little in the opposite direction. Finish closing the cover by using the front part of the mighty crimpers to squeeze it shut while keeping the crimp cover round.