This is a simple method which works. I've used this in relatively high wind situations.
https://survivalcommonsense.com/keep-tarp-grommets-for-ripping-out/There is a text description of how to do this, but the video (2:00 min) is better. Unfortunately, it does not show the actual usage, but you can figure this out yourself.
The intent is to spread the load across three grommets , the center grommet must be on a tarp corner. This doesn't work well if you use three grommets on a straight side.