I made this dress for a Titanic Party last year. The sewing process was a lot of fun and the party was amazing!

Step 1: Purchase a Sewing Pattern

For this dress, I used the burda style magazine pattern "6/2010 Long evening dress with "jeweled" shoulders #118", available here:
http://www.burdastyle.com/pattern_store/patterns/62010-long-evening-dress-with-jeweled-shoulders

Step 2: Cut Out Pattern Pieces

Cut all the pattern pieces twice (in satin and in tulle). Cut the tulle layer for the skirt about 0,5-1,0 meter longer than the satin skirt piece.
Lay the tulle pattern pieces 21-24 (for the top of the dress) on top of the right side of the satin pattern pieces and stitch them togther (or pin). Continue sewing as if the two layers were one pattern piece.
Do not stitch the two layers of the skirt together yet.

Step 3: Cut Out the Slit in the Front of the Tulle Skirt

Take a piece of paper and draw the shape of the narrow slit for the front of the skirt. Lay out the tulle on the fold, also fold your paper piece for the slit in half (lenghtwise), pin it at the top edge of the tulle skirt piece and cut out the slit in the tulle.

Step 4: Cut Out the "curve" in the Front of the Tulle Skirt

Take a big piece of paper (or tape together a couple of smaller pieces) and draw the shape of the curve for the cut-out in the front of the tulle layer of the skirt.
Once you have the right shape drawn, cut it out from the paper, fold it lenghtwise and lay it on the folded tulle, about 3 cm beneath the slit you just cut. Pin it and cut it out.
Sew on the trimming around the edge of the slit, then stitch the two skirt layers together and handle them as one layer in the following sewing process. Sew the dress using the instructions from the burda style pattern.

Step 5: Cut-outs in the Front

This is how it will look like in the end.

Step 6: Sew the Dress

Sew all of the pattern pieces together according to the sewing instructions for the sewing pattern.
Hang the dress on a hanger and cut the train (the tulle layer of the skirt) in a nice round shape.

Step 7: Sew on the Trimming and Embellishments

This is probably the most time consuming part of the dress.
Sew on the trimming around the edges of the tulle train, at the bottom edge of the satin skirt and at the edges of the shoulder pieces and apply the embellishements on the top part of the dress.
I intended to put a lot more trimming on the whole dress but I just didn’t have enough time.

Step 8: Sleeves

For the sleeves, measure your upper arms and write down how long and wide you want your sleeves to be (consider they should be wide enough to attach them to the armholes of the dress). Cut out two rectangles (according to your measurements), stitch together the longer sides of them, you will have two tubes.
At the opposite side of the seem (on the visible part of the sleeve), hand stitch a seam and gather up the tulle.