This region of China is known for textiles and embroidery, so it isn't a surprise that Chongqing has a huge selection of tailors. They can make clothing in 2–3 days, for very low prices.
Some tips for tailoring clothing in Chongqing:
—You usually get what you pay for. Most tailors close to Liberation Square are a little pricey, but the quality is good, they usually speak some English, and they'll even deliver to your hotel. The tailors down in Ciqikou will be cheaper but more of an adventure.
—Chinese tailors seem to make suits and qipaos (a traditional form of dress) the most. That doesn't mean they won't make anything you want, but you'll probably have the most luck with a copy of something you own—a photo might work, but it's hit-and-miss.
—A tailor will ask you to choose a fabric, then take your measurements. At the end, they'll give you a price; most people don't haggle over this. A simple shirt can cost around 80–120RMB, to give a you an idea of cost. You must pay part of it as a deposit, then the rest on pick-up.
—Specify as many details as possible, especially with formalwear. I usually buy my own buttons, zippers, and even thread in advance, because the materials the tailors use are often cheap and not good quality.