This is my next beginner crochet square, following the single crochet one. I suggest you master single crochet before you continue with double. The main difference is the size because double crochet is about twice as long as single crochet. Good luck!
Step 1: Materials
For this project, you'll need medium/light colored yarn, crochet hook size H-J, tape measure/ruler, darning needle, and scissors.
Step 2: Beginning Chain
This is the same as the chain when we started single crochet: wrap yarn and pull through loop on hook. Work 12 chain stitches.
Step 3: Double Crochet Stitch 1
Wrap yarn around the hook from the right to the left going under the hook and over the chain.
Step 4: Double Crochet Stitch 2
Insert hook into the 3rd chain from the hook. (remember, the 3rd "v" from the hook) (also remember, into the top half of the chain) Make sure the yarn is in between the two loops on the left side of the hook.
Step 5: Double Crochet Stitch 3
Wrap the yarn from the left side of the hook to the right side, going over the hook and between the two loops.
Step 6: Double Crochet Stitch 4
Wrap the yarn behind the hook from right to left, in front of both loops. (In order from left to right: wrapped yarn, loop from chain, wrapped yarn, loop from end of chain)
Step 7: Double Crochet Stitch 5
Like we did with single crochet, pull wrapped yarn that's closest to hook through FIRST loop only. It will now look like there are three loops. (In order from left to right: loop that you just pulled yarn through, wrapped yarn, loop from end of chain)
Step 8: Double Crochet Stitch 6
Wrap yarn as before, this time pull it through both the FIRST loop and the SECOND piece of wrapped yarn on the hook. There will now be two loops on your hook.
Step 9: Double Crochet Stitch 7
Finally, repeat step 6 one more time so there is only one more loop on the hook. One finished double crochet stitch! You should be able to see the "v" on top of the stitch.
Step 10: Continue the Stitch
Now you will repeat steps 3-9 on the next "v" on your starting chain. (Do not skip two "v"s like you did in step 4: that's only at the beginning of rows.) In this picture, I have done 3 double crochet stitches, notice 3 "v"s on top.
Step 11: One Finished Row
When you finish with the "v"s on your chain, there should be 10 stitches like shown in the picture.
Step 12: Turning for Next Row
Now work two chain stitches at the end of this row to continue to the next. Turn work and repeat steps 3-9 across, crocheting 10 double crochet stitches.
Step 13: Continuing the Rows
This is what two rows looks like. Make sure you're counting the "v"s at the end of each row to make sure you always have 10.
Step 14: When to Stop
Use your tape measure to know when it's reached a square. Mine ended up about 2 3/4" long. This for me was about 6 rows. This can be different depending on the yarn/hook.
Step 15: Finishing Up
End it just like you did for the single crochet square: pull the loop large, cut yarn, pull through loop, pull to tighten. Sew in tails like before also through fabric.
Step 16: You're Done!
You've successfully created a double crochet square! Make a bunch of them until you get the hang of it, you'll get better over time. Now that you know double crochet stitch, my next tutorial will teach you how to make a square that involves increases and decreases.