I need some help, again 🥲

Hi everyone. Me again.

A couple of days ago i posted a doubt i had about re-felting a friends old pool table, and all the help i got from that video was very useful.

I couldnt finish in one day due to the amount of things i had to do (my friend wanted to give it a new coat of paint as well) but when it came time staple the new felt, i found myself with a new problem.

The felt my friend got (based on the avaylability of Argentina in our region) is probably 100% poliester and it wont strech (i saw that in the US there are a few that are a mix of 75%wool,25%poliesther).

For the guide on how to proceed i was using this video (https://youtu.be/s4mH1Lw104I?si=OIBkGrAKeFM2_RsM) and in it the host talks about certain marks that he makes that are useful when you strech the cloth (the exact ones that come to mind are the marks at the sides of the anchor and strech side center pokets, one was 13/16 and the other was 5/8.

Do i have to keep them in mind or do i just simply make sure the cloth is tight and staple it to the board without making them?

Again, all help is much apreciated. Have a nice day!