I can't figure out how to resize the signature box in Adobesign

I've checked in preferences for the ability to resize it and I don't see it there. If I hover over the signature box, all I get is crosshairs and it lets me move it, but not resize it.  If I right click, I get a delete and an edit option.  The edit option doesn't let you do anything.  Surely, there must be a way?