Trial and Error, practice makes perfect
I'm discovering that I am a trial and error kinda person. Despite my attempts at being a perfectionist and my obsession with detail, I still just go full speed ahead without thinking some stuff through. So after choosing my background I rushed home from the fabric store and pinned my piece to my new purchase and stitched. After completing the applique and confidently cutting away the back fabric from behind my piece I stand back to look. Ok...so why won't it lie flat! I think, no problem, I will make it lie flat when I stitch it. Then I realize, I sewed it onto my background square CROOKED. which actually lead to other issues that created the rippling fabric issue. I now realize things will only get worse from here! So I start again, unstitch my mandala piece, cut a new backing, and this time draw registration marks so the circle will lie flat and be straight!