[quote=CoriAmD]I use a circle template to trace onto interfacing, then sew this (right sides together) to the fabric I want for the center. Trim around with pinking shears to about 1/8" .. Cut small slit in interfacing and turn. Press well. ]
Ditto to this post. I also sometimes save used dryer sheets instead of interfacing. I use this method for Dresden centers and for Buggy Wheels, too. For Buggy Wheels centers I make a 4 patch first then cut my circle from that so it has 4 pie shaped pieces for a more scrappy look.