I just cut the length wide enough to fit down in the pot, used 2 layers for the first one, decided to use 3 layers for the second one.
Just layer the mesh in the pot, an extra hand would help as the deco poly mesh naturally holds it shape and would curl up around the edges.
Add your potting soil, making sure you have plenty of width to hang over the edge until you're through potting. Don't trim the edges until you have your plants snuggly in the soil.
Trim the excess mesh.
Once the flowers have grown and filled out more, I'll take more pictures and post. I'm sure it will be necessary to keep a close eye on the moisture content as the pot will dry out quick (same as it would with the cocoa mat).