I'm reposting this written tutorial from a few years ago to let you know that I've added a video tutorial. The video demonstrates the Foundationless double crochet in both worsted weight and bulky weight yarns, as well as a foundationless single and half double crochet technique.
Many of my designs start with the DcChain or Foundationless Double Crochet shown and described below.
I thought I'd share with you one of my favorite techniques. Instead of starting every project with a chain strip, using a "foundationless" stitch can speed up the start of your project and allow for more stretch than a starting chain would.
A foundationless DC, or DC Chain, is my favorite way to start a simple, lengthwise scarf. It is also good for garments that you crochet from the bottom edge up, since it creates a stretchier edge as compared to a starting chain. It's easy to change a pattern that calls for a starting chain and then a row of DC. Just work a row of foundationless DC (or DC Chain) instead.
Start with a Ch 3 (this chain 3 counts as your first DC stitch). YO, insert hook into the first Ch, YO and pull through. YO and pull through one loop to create the "base chain" (3 loops remain on hook). Now work a DC as normal - YO and pull through 2 loops, YO and pull through last 2 loops.
See the picture above - the last chain made under the hook is the "base chain" and the double crochet will be on top of it, next to the starting chain 3.
To work the next DC Ch, YO and insert the hook into what was the last "base chain" stitch (it's actually a ch 1 at the base of each stitch). To make this easier to find, I usually hold that stitch as I'm finishing the DC so I know where the chain stitch is when I move on to the next one.
YO and pull through, creating the next "base chain". (Hold this stitch if you want to to mark it.) Then work the DC - YO, pull through 2 loops. YO, pull through last 2 loops. Continue working DC Ch for as long as you want your project to be.
So each stitch consists of a base chain (like a ch 1) and finishes with a double crochet, all in one stitch and the beginning chain 3 counts as your first DC.
I have incorporated this stitch in the foundation of my Circle Shrug Vest Pattern, the Long Fingerless Gloves pattern, for the hood on the Wildwood Capelet Pattern, and the Chunky Crochet Button Wrap pattern.