I did not do this mind you. I was talking to another member about this in the past and what they did was use something like the tip of a compass (the circle drawing kind, and Icepick or something similar might work) and he worked it between the individual threads and then spread them apart as best he could, then insert the grommet pieces in the holes made. Depending on how tight your fabric is you could do that and then you wouldn't have to punch holes or cut fabric which would probably hold up longer. The other way is just punch away, but no mater what you really want to install the grommets.