Blocking Gaps From Window A/C Unit

I just recently had my window air conditioner installed by a friend. There is always a gap that needs to be taped or something every year. I used duct tape and it came out really messy. Today, I did the living room one with the self sticking plastic. It came out perfect and hardly showed. I don't know how long this method will last but we will see.

By Kathie L. from Portland, ME