I talk a lot on this blog about the versatility of separates. Here, from 1949, are some examples of how sewing separates can give you the look of a dress. And, may I just say, I love the little floral posy as an accessory. Pinned at the waist or at the bottom of a V-neckline, they add a touch of whimsy to these outfits. You can find posies like these by doing a search for "vintage millinery flowers" on the web.
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Sewn from 1949 Advance pattern number 5173. The V-necked halter top and full skirt worn together give the impression of a dress. Add a short sleeved jacket when the air-conditioning is too cold.
Advance pattern 5173 from 1949
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Here, sewn from Advance pattern 5174 from 1949, a sleeveless blouse is matched to a full skirt to make a dress. A self-fabric belt is worn at the waist.
Advance pattern 5174 from 1949