To work in single crochet spike stitch, you will need to work 2 rows in single crochet first over an even number of stitches.

Take the 2nd colour and make 1 chain stitch (this is your turning chain and doesn’t count as a stitch).

Instead of inserting the hook into the stitch of the first row, work into the foundation chain below that stitch. Pull the yarn through, then pull it up to the top of your crochet piece, then complete the stitch as if it were a normal single crochet stitch. Don’t pull the yarn too tight.

To work the next stitch, don’t work into the stitch on the first row, work into the stitch on the row below, pull the yarn through then pull it up to the top of your crochet piece, then complete the stitch as if it were a normal single crochet stitch. Don’t pull the yarn too tight.

Repeat steps 3 and 4 to the end of the row.

Work the next row with your 3rd colour, make a chain stitch (this is your turning chain and doesn’t count as a stitch).

Instead of inserting the hook into the stitch of the first row, work into the stitch 2 rows below. Pull the yarn through, then pull it up to the top of your crochet piece, then complete the stitch as if it were a normal single crochet stitch. Don’t pull the yarn too tight.

To work the next stitch, don’t work into the stitch on the first row, work into the stitch on the row below, pull the yarn through then pull it up to the top of your crochet piece, then complete the stitch as if it were a normal single crochet stitch. Don’t pull the yarn too tight.

Repeat steps 7 and 8 to the end of the row.

Work 1 row in single crochet.

Repeat steps 7 to 10 with the 1st colour. Repeat steps 7 to 10 with the 2nd colour. Repeat steps 7 to 10 with the 3rd colour. Repeat these 3 steps to continue working in Single Crochet Spike stitch.