Tension is very important, the yarn must be able to glide smoothly from your left hand to the working project, not too tight not too lose.
You will need the following:
Step 1: Start off with a slipknot.
Prepare your yarn tensions on your left hand (right either whichever is your orientation).
Step 2: Chain 12.
Step 3: Counting from the last loop on the hook (don’t count the loop on the hook). Yarn over then insert hook into the top loop of the fourth chain.
Step 4: Yarn over and pull up a loop.
Check: Now there are 3 loops on your hook.
Step 5: Yarn over, and pull the yarn through two loops.
Check: Now there are 2 loops on your hook.
Step 6: Yarn over, and pull the yarn through two loops.
You have just made your first double crochet.
Step 7: Yarn over and insert hook into the top loop of the next stitch.
Step 8: Repeat Step 4 to 6 all the way across your foundation chain.
Step 9: To start the next row, chain 3. This will count as your first double crochet. Skip the next stitch as it belong to the turning chains.
Step 10: Yarn over, and insert hook into the next stitch.
Step 11: Yarn over and pull up a loop.
Step 12: Yarn over, and pull the yarn through two loops.
Step 13: Yarn over again and pull through the last 2 loops on your hook.
Repeat steps 10 to 13 all the way across to finish the row.
And there you have it. You should have 9 proper double crochet and 1 turning chain, a total of 10 stitches for each row.