Wear thick work gloves and goggles for safety.
Wood sealer will help the putty or glazing compound adhere to the wood and will help with weather-proofing your windows.
Don’t worry about laying too much putty or compound because you’ll be scraping the excess away later. You can purchase putty or a glazing compound from the hardware store or online.
Remember to smooth the putty on both sides of the window.
Applying tape to the crack should temporarily stop the window from cracking further.
Clear nail polish will only seal small cracks and holes in your window and shouldn’t be used for windows that have sustained significant damage.