In my desire to make myself some glorious garb, and the fact that each time I'm begging my husband for assistance to see what it fits like to tell me how many inches it needs in the adjusted at the hem, what the measurements are on my bust, etc. etc. I went shopping for a mannequin, but in addition to the fact that none of them really were shaped like me, they were very expensive.
So I went to my trusty stand-by when I want to do something but have no idea how. Pinterest! (haha) I found this on a Russian website, but delightfully simple photos helped me know exactly what I needed to do.
In case you don't have a google translator or have questions, here's my quick run down. Take a t-shirt, one that's snug and long - mine was an old one I had in my drawer so I got it for free. Put it on. Have a friend tape you up snugly and smoothly (some wrinkles are workable.) I used about 3 rolls ($15) of tape on mine, but I am definitely larger than their model. You'll note on the photos that they secure under the bust with a circle of tape, and they also drew a line around the waist where you bent. I didn't understand why until I cut up the back, but do it, it helps a lot.
When you are fully taped, snugly and securely, have your friend take a pair of scissors and slice it up the back. You want to align these marks to ensure that its straight.
When you pull it off it will keep your shape very well. Start by putting cardboard in the sleeves and neck. Then tape them into place. When you have capped them and secured the back stuff it. I filled mine with a hodge podge of a bunch of different things, cardboard, newsprint, stuffing, and chipped foam. The best thing I found was the chipped foam, but I'm glad I did a variety of them as it would have taken a lot more to fill it with just the foam. I ended up spending about $15 on the foam and stuffing, and cut apart two horrible old lumpy pillows that needed to be replaced anyways.
To make the stand I spent $11 on wood, $8 on the 4x4, I cut it down to roughly my heighth. Then $3 on a 2x4. We cut this into roughly 16 inch pieces, and screwed them into place, taking some care to make them as level as possible. (We already had the screws.) And you're set, for less than $50 you'll have a mannequin that fits you to a tee.