I've been wanting a romper for quite a while now, so here's how I made my own. I used about 1.5 yard of a heavy knit purchased at Joann's and some half inch wide elastic.
I started by making the shorts of the romper using a pattern I previously made as seen in my high waisted shorts post, and essentially made them with the pockets as I did before, with the exception of not adding the waistband and extending the top of the shorts higher by an inch or two.
For the back of the shirt part, I followed the basic shape of a loose fitting shirt I already own, also adding some length to the bottom. I matched the width of the top to the width of the opening of the shorts. For the front of the shirt, I traced the same shape onto two layers of fabric, and then drew a diagonal line across one shoulder to the opposite bottom edge. (Make sure the two layers are right sides together so you get a left and a right piece, unless the fabric has no right or wrong side.) I later adjusted this diagonal until I got the shape I wanted. I hemmed the angled edge and connected the bottom of the two front pieces and then connected the sides and shoulders of the entire shirt by sewing the two parts right sides together.
To connect the top and shorts, I left the shorts right side out and turned the shirt inside out over the shorts, matching up the edges of the openings. I pinned around the opening and sewed around it.
Next I measured the elastic to fit my waist and sewed the ends together to make a circle. I pinned the elastic around the waist, stretching it as I went along, and then sewed the elastic down.
Lastly for the sleeves, I traced the general shape of the sleeve onto some fabric, using the arm opening of the romper as a guide and adding a seam allowance. I hemmed the edges, and then folded them in half, stitching the shorter edge together. To attach the sleeves, I turned the romper inside out and left the sleeve right side out and pinned around the curved edges.
Once everything is all put together, that's it. It's super comfortable to wear and the wrap front top opens to make it really easy to put on and I think it's perfect for summer.