Hey guys...I have been trying to fix Lumas dresses from Bella's Prissy Puppy and its taking the forever just to sew on some extra velcro

not only that, I finished one dress and it fits now but the proportionss are so off it looks ridiculous. I'm really upset.
Anyway, to ensure this doesnt happen again I got a tape measure and want to take her measurements. How do I do this thhe correct way? Mostly for dresses/dress harnesses.