Crochet is a wonderful craft that allows you to create beautiful and practical items with just a hook and some yarn. One of the simplest and most versatile crochet projects is the humble coaster. Coasters are a great way to practice your crochet skills, and they make a lovely addition to any home. In this article, we'll show you how to crochet a coaster step-by-step.

Materials:
- Worsted weight yarn (any color of your choice)
- Crochet hook (size H-8 / 5mm)
- Scissors
- Yarn needle

Step 1: Create a Slip Knot
Begin by creating a slip knot. Take the end of your yarn and create a loop. Insert your hook through the loop and pull the end of the yarn through to create a slip knot. Tighten the knot around your hook, leaving a small tail of yarn.

Step 2: Chain Stitch
Make a chain of 5 stitches. To do this, wrap the yarn around the hook, then pull it through the loop on the hook. Repeat this process until you have 5 stitches on your hook.

Step 3: Join the Chain
Insert your hook into the first chain stitch you made. Wrap the yarn around the hook and pull it through the chain stitch and the loop on your hook. This will join your chain into a loop.

Step 4: Single Crochet
Begin the first round of single crochet stitches. To do this, insert your hook into the center of the loop, wrap the yarn around the hook, and pull it through the loop. You will now have two loops on your hook. Wrap the yarn around the hook again and pull it through both loops on your hook. This is your first single crochet stitch.

Make 1 single crochet stitch in each chain stitch of your loop. This should result in 5 single crochet stitches total. When you reach the end of the round, insert your hook into the first single crochet stitch you made and make a slip stitch to join the round. Cut the yarn, leaving a small tail.

Step 5: Switching Colors (Optional)
If you want to switch colors for your coaster, now is the time to do it. Take your new color of yarn and create a slip knot. Insert your hook into any stitch of your previous round, then pull the new yarn through the stitch and the loop on your hook. You can now use the new color for your next round.

Step 6: Half Double Crochet
Begin the second round of stitches by making a chain stitch. This will act as the first stitch of the round. Make one half double crochet stitch in the same stitch as the chain stitch. To do this, wrap the yarn around the hook, then insert the hook into the same stitch as the chain stitch. Wrap the yarn around the hook again and pull it through the stitch. You will now have three loops on your hook. Wrap the yarn around the hook again and pull it through all three loops on your hook.

Make one half double crochet stitch in the next stitch, and then repeat this process around the entire coaster. When you reach the end of the round, insert your hook into the top of the chain stitch you made at the beginning of the round and make a slip stitch to join the round. Cut the yarn, leaving a small tail.

Step 7: Finishing Touches
Using your yarn needle, weave in the ends of your yarn to secure them in place. Trim any excess yarn.

Congratulations, you've just made a crochet coaster! Experiment with different colors and stitch patterns to create a set of coasters that are uniquely yours. Happy crocheting!