Before we begin, there are two things I consider an asset when sewing is (a) an iron for pressing as I go and (b) thread to match fabric. (I'm using white for this tutorial in the hope you will see it.)
This dolly dress makes up best when using finer fabrics, like Tana lawn and Japanese cotton, and the latter is what I have chosen.
The measurements for this dress are easy to measure for any size. Determine the finished length you want by measuring your doll from shoulder to knee or where you would like the hem to be.
For my LittleFee it was 12cm, then you must allow for the casing (the size of the casing will depend on the width of the ribbon you use. I'm using 6mm ribbon so I allow another 1.5cm) and hem (another 2.5cm) giving you a total of 16cm. The width I use is simply double the length, so I will cut a piece 32 cm long by 16cm wide.
Fold the fabric in half, like so, then cut the fabric in half up the side.
Fold each side over 5mm and press it down with your iron, then stitch each side.
Now put right sides together and measure the length of an armhole plus the top casing allowance and mark it with a pin. In my case I allowed 4cm from the top to the pin. Should you be unsure how big it should be, measure one of your doll's tee-shirts.
Sew both sides of the dress from the pin, to the bottom edge. Then open both seams all the way from the bottom to the top and press flat.
Next, make the casing for your ribbon on front and back top. Fold the fabric down 5mm and press. Fold the width of your ribbon plus approximately 4mm down again and iron. Stitch them both down along the bottom of the casing.
For the ribbon, you may use a piece on each side twice as long as the dress is wide. Or for a different look, one piece three times the width, which is what I'm doing so I have one bow on the shoulder. Attach a safety pin to the end and feed the ribbon through the casing.
For the two separate ribbons, I fold the dress in half and make sure the ribbon is equal on each side, then sew a little seam in the middle of the casing to hold the ribbon in place. Heat seal the ends of the ribbon to prevent fraying. To do this, hold the ribbon near a flame, but not so as it burns, just to melt the end and seal it off. If this scares you, just tie a little knot at the end of each ribbon.
Now to hem the dress. Fold up from the bottom 5mm and press. Fold up another 10mm, press again then sew the hem down, either by machine or hand using small stitches (which is what I will do).
You can pop a long sleeve skivvy underneath for cooler weather or make a shorter version and pair with shorts or crop pants! Of course if you were using plain fabric, you can always trim with lace or ricrac.