Using my floral knife, I carefully cut around the imprinted portion where the glass will rest.
I life out the foam, creating an indentation that the glass bottom will fit down into.
Wet foam molds easily, so I flatten the unlevel surface with my fingers first, then firmly press the glass stem down on the indentation, creating a flat, level surface for the glass to rest in.
You can skip this step if you'd like, I just like the feeling that my glassware is firmly seated on top of the foam.
Taking another short block of wet foam, either press it against the glass stem or notch out a section with your knife.
Do the same for a second piece of foam and then fit both pieces around the glass stem as shown.
Notice I placed another piece similarly on top of the lower glassware stem as well.