I am making a dog dish holder, and need to cut some 6" holes out for the
dishes. I have tried a jigsaw and hope to find a better method; I didn't
get the line quite perfectly. Well, not even close, actually.

I need to cut a few, so spending a few dollars is not objectionable. Any
suggestions would be appreciated. I mean, other recommending that I get
better with a jigsaw.