Here are two sheath dresses I made from a vintage 1958 pattern, Advance 8617. The yellow “tropical dress” has kimono sleeves and the fitting is more relaxed in general, and I think it is better for it. The blue dress has gussets in the sleeves and a more fitted bodice. The original 1958 pattern was much too big and I re-sized it to my size. My weight has shifted slightly since cutting the pattern, so the fit was no longer perfect, a good learning experience for the next dress. (Don’t wait 8 months between cutting and sewing!) I ended up taking in the bodice side seams a little and lengthening the darts slightly.

View 3, Advance 8617 from 1958 – my “tropical dress.” I made this dress second. The kimono sleeves give it a more relaxed fit. Notice that the waist falls in the right place in this version.
What I found in the test run with this pattern: This dress is best in a very lightweight cloth with good drape, especially silk, chiffon or rayon. The pattern is more roomy than expected, leaving space to take it in or let it out later.
The inspiration was Joan’s dress from the accordion scene in Season 3, Episode 3 of Mad Men, see photo below. But obviously I am not shaped like Joan, and few people are.
Tropical dress – I imagine myself wearing this dress lounging on a warm and breezy veranda sipping hibiscus cooler. Since I’d be lounging, who needs a belt?! So I set aside the belt hardware and I did not make the self-fabric belt.
Blue dress – I like the shorter sleeves and the more fitted upper body, but the extra time to do the gussets was not really worth it. Short cap sleeves or very short kimono sleeves might look just as nice and save a lot of time.
Technical alteration details:
Both of these dresses are test-runs (wearable muslins) of each view before I purchased more expensive silk or rayon. What I changed:
– To re-size the pattern down, I took a total of 4 inches out of the pattern, with a 1 inch vertical tuck in all pattern pieces, through the shoulder to waist to hem. This did not reduce the neckline.
– I shortened the back waist length by 1 inch in the blue dress and 1.5 inches in the yellow dress.
– I lengthened the bust darts by 1.5 inches and lengthened the skirt darts by 1.25 inches
– I reduced all skirt seams to half an inch.

View 1, Advance 8617, from 1958 – I made this dress first. It has gussets in the sleeves and a more fitted bodice. This blue cloth is a more retro look, but the yellow West African print was probably around in 1958.

View 3, Advance 8617, from 1958 – my “tropical dress.” I made this dress second. The kimono sleeves give it a more relaxed fit. Nessa has the best expression in this photo! She looks skeptical.
Specific fitting issues:
My back waist length is about an inch short compared to most “standard body” measurements, so I always shorten patterns in the upper torso. Also I usually use a pattern with a bust measure that is two to four inches smaller than my actual bust measure. I do this since my ribcage, back, arms and shoulders are smaller than average compared to “standard body” measurements. I need for these critical areas to be fitted; I expand out the other areas that need it. It makes more sense to expand out one area than take in four hard-to-fit areas. Otherwise I’m swimming in the bodice even through the chest measure is correct.
What I found:
This pattern allows a lot of ease. Even though I took the pattern in to a bust measurement that was an inch smaller than my actual bust measurement, as you can see, it is still quite loose in the bust. If I wanted it to look like Joan’s dress, I would have to take in the bodice much more all around.
View 3, with the square neckline, has a huge neckline! It is barely off the shoulders. While I wanted an open and tropical look, this is just too open. In retrospect, I know that I should have fitted the shoulders to my narrow shoulders, which would have also solved the too-big neckline. Or, I could have just taken in the neckline by a couple of inches.
In the first dress (blue), I shortened the back waist length by an inch, but that was not enough even though the measurements should have been correct. So in the second dress (yellow), I shortened the back waist length by 1.5 inches.
No surprise, my upper body is smaller than the lower body. I fixed this simply by reducing all skirt seams to half an inch or less, which adds a total of five eighths of an inch + around the hips. (The skirt had already been taken in 4 inches when it was re-sized become my size.)
I could have had a more detailed approach to sizing down the pattern, but since the sleeves and shoulders were loosely fitted, I thought the vertical tucks in the pattern would work out fine, and they did.
Summary:
I will make this dress again, however I will not wear it to an event where I plan to eat a lot (!), because it is fitted in the midsection. This dress is best in a cloth with a nice drape and a slight stretch, and I will certainly make the square neckline smaller so that it stays on my shoulders.