I always cut foam core board with an X-acto knife with a sharp, never-been-used-before blade. Making straight cuts is difficult, good luck with a circle! Try to do a practice area, to get a feel for how it cuts.
Any kind of glue for paper should work to glue cardstock to the foamcore, since the faces of the foamcore are made of paper.
__________________ Alice
[COLOR="DeepSkyBlue"]>^..^
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