When I was buying men's shirts I used to buy them large or medium, so I tried medium blouses and dresses in women's wear. I found they often looked too loose, so I sometimes even buy misses small. The first time I tried to figure out an online order I decided I was about a size 14. That was way off, so I tried various sizes and even found a size 12 skirt was way loose on me. Now, depending on my fluctuating waistline, I can wear between an 8 and a 10 in pants and skirts.
Uppers and dresses often tend to be more forgiving than waist-dependent items. Think about whether you want the garment to be snug or loose. Also, manufacturers seldom seem to adhere to strict sizes across brands or even on the same assembly line for one brand. So trying of first is best. If not, buy from one of the mail order houses with great return policies (some allow returns of clothes for up to 3 months).
Lyric