Starcraft 1990 How To Make Canvas On Pop-up Stronger?

How to make canvas on pop-up stronger? - starcraft 1990

I have a 1990 Starcraft pop-up. I have cleaned in preparation for a family camping trip, when we noticed that the screen begins to be quite low. I had started 2 above points. I am willing to test the waters and do not know if it's maybe a little more, which are applied to fabric take to longer and a little louder?