Fixing Windshield Cracks

The first step is to remove any loose debris in the crack and any glass. You can use a razor blade to scrape out the crack gently to make sure noting remains inside.
Wash your windshield to remove any leftover loose particles and shards of glass
After reading the instructions that came with the kit because each kit differs slightly. The main tool has suction cups, which are put over the windshield crack but make sure that you can still see the crack through the center of the tool.
Once you have the tool firmly in position apply resin into the center of the hole. The kit may contain an extra tool that will properly apply the resin and remove any air bubbles that appear after applying.
After filling in the crack it needs to completely dry. Do not remove the tool. You can let your car sit in a dry warm area to help harden the resin. The resin will be a clear thick mass after it has hardened that will stay firmly stuck in the windshield crack.  Once it has hardened you can remove the tool
Check the crack to see if you need to repeat the treatment. If it is a deep crack, you may need to do it again.
Once you are satisfied with the repair of the windshield cracks you should take a soft dry cloth and polish the area so the resin solution will match the glass around it as much as it can. If you were fixing a small crack it could become almost unrecognizable and appear new to the naked eye but if it is a large crack it could look slightly warped in the area where it was fixed.