Let me first explain my pattern-making
skills ways: I taught myself everything I know...pretty much by trial and error and by understanding how the pieces fit together and how they then fit on the body. So this is just how
I do things.
I have this basic t-shirt pattern and I swear it's a Mccalls (I can't seem to find it right now) but I can't find it on their site so it may be out of print. But I know that the sz.M fits perfectly so I use that as a guide for all my patterns. So maybe you have a pattern like that or a shirt that you know fits you well that you can use. Here's my paint shop skills at their finest:
This is basically what I did

The gray drawings are what it looks like finished and the skirt of the front and back have gathers at the center along with the bodice at the bust.
First-I stand in front of the mirror and pin the pattern piece for the front to my shirt and I lightly use a pencil to draw where I want the lines to go. How much I want it to slope in-ward and how low I want it to sit and everything. Then I un-pin it at use a ruler to make the lines straight. For piece #1 I make sure I add 5/8" seam allowance in the center (where they usually have you put it on the fold, you know?). I cut four front pieces.
Then- I cut the piece that goes from under the shoulder and up to the neck (the purple piece). Cut four of these.
Then- Stitch the purple pieces on the all the front pieces. Then take the left front and the piece thats going to line it and sew then right sides together, leaving the bottom and the seam that goes under the arm unstitched. Do the same to the other front pieces. So now you have the two pieces for the front (both are "lined" or whatever).

1. These two edges should be raw, the rest are sewed to the "lining".
2. Stitch across the red line to make the casing for the ties neck
3. Use a seam ripper to unstitch where the blue is (between the casing seam and the neck) so the ties can slide through.
4. Gather between the yellow lines
Cut some fabric for the ties and put them in.
The back part of the bodice is put together pretty much the same way as the front. Just cut two of the main color and two of the contrast color and stitch them together. Seam the sides of the bodice.
The waist band should be cut to fit around under your bust plus 1 1/4" for the seam. Seam the waistband at the two smaller edges and attach the bodice. I add 2" to the skirt on the fold to allow for gathering. Seam the skirt at the sides and gather at the top center and attach it to the waistband. Hem and you're done!
I really hope all that made sense.