I also happened to be broke, so I was determined to make the outfit out of materials I already owned.
Here's what I used:
1 small womens pink shirt (cost $1 at the dollar tree, which I had previously purchased)
1 Large mens Black shirt
1Large mens White shirt
White thread
Fluff from a pillow we own
Cardboard from empty snack boxes (that I save for all kinds of crafting purposes)
Pink duct tape
black tights
I spend 25+ hours hand stitching each seam, attaching each dot that I had free form cut from the white T-shirt, fashioning a little white collar, giving her one black stitched heart patch, creating the perfect (and totally made up) puff sleeves, which I remade twice out of the same material.
The first picture was my first attempt at the sleeve. I wasn't happy with it, so I pulled out the stitches and added white panels, then cinched the top and bottom of the sleeve hoping it would make it a little more puffy. It totally worked!
For the skirt, I really just had to sew on as many dots as it took to look good. There was no real pattern, I just spaced them out as evenly as possible. It was very time consuming, and made my hand hurt. :) Finally I cinched the top of the skirt in 4 placed and added a long strip of white T-shirt in order to adjust the size as needed once it was done. And also to have enough material to make a big bow in the back.
The results, a perfect Minnie Mouse. I shocked myself by how well it turned out when I have very little sewing experience. All I had was a vision in my head and a desire to make it perfect for my almost 2 year old!