I had a lot of fun making this romper out of some ridiculous pants I found at my thrift store. The pants are a kelly green knit and they are vintage Express. They are pleated in the front and have side pockets, and had a really pronounced taper at the ankle. They are elasticized at the back.
So I made the top part out of jersey, it's just a really basic double scoop. I sewed on the shorts just like you'd sew a skirt to the waist of a dress and I hemmed the pants into shorts. That was it! The jersey is stretchy and the pants have elastic so it just slips on! It's pretty comfy. You just have to make sure the torso of the top is long enough so the shorts don't ride up haha.