Following are simple instructions for how to make a paperbag dress. . My dd is a 4T, and she likes her dresses below the knee for reference. I just measured her and eyeballed most of this.

The finished dress:



Step 1: Cut out your rectangles. I used every last bit of length on the main fabric that I had, so I used a border to make the dress longer. My main fabric rectangles were 22" tall x30" wide. I probably could have gone less full. I'm sure the original was. This gave me 5" for the paper bag portion at the top. Add whatever extra you'd need for a hem if you don't do a contrast band. My band pieces were 6"x30". I folded them in half instead of hemming.

Step 2: Sew and finish side seams. I was too lazy to look for all of the parts of my serger, so I just used French seams. ;) Use whatever method you want to finish them. This is a forgiving dress style.

Step 3: Either hem the bottom of the dress or add a band like I did. (This pic is of the folded band with the raw edges lined up with the bottom of the dress. I then sewed a seam, pressed the SA up towards the body of the dress, and topstitched.



Step 4: Fold the top down 1". (1/2" would easily do if you're short on fabric. It just has to be enough so that the raw edge is enclosed in the casing.) Then fold it down 4". Sew a hem there. Be sure to leave 2" or so open by the side seam so that you can put the elastic in the casing that you are about to make.







Step 5: Mark a pencil line for the top edge of the casing. This is on the inside of the dress, so I just used a faint pencil line. I made mine 1.25 inches because I was going to use 1" elastic. Sew on this line all the way around the dress. Feed the elastic through and close up the opening.





Step 6: Make and attach straps. You'll need to position these on the child. Mine ended up being 15", and I zigzagged the ends and folded them so they would be inside before I attached them. They're pretty long because I anchored them both above and below the casing on the inside making sure that they did not obstruct the elastic's movement. I positioned them by pinning them on while my model was wearing the dress. I didn't get pics. Sorry!

Step 7: Make and attach belt loops. I eyeballed the placement on these just above and below the casing line and centered on the shoulder straps.

Step 8: Make belt. You could also just use ribbon.

All done! Hope this helps!