Crocheting with Foundation Single Crochets and Long Single Crochet Together

1st and 2nd Rounds
Begin with a round of fsc - foundation single crochets (fsc) (any multiple of 3 + 2). In my tutorial example, I started with a round of 50 fsc. At the end of the 1st rnd, join to the beginning stitch with a slip stitch. For the 2nd rnd, work 1 single crochet in each stitch around, but do not join at the end.
3rd Round
Work 1 single crochet in each of the first 2 stitches. Mark the start of the round with a stitch marker. Working back over the 2 single crochets just made, insert the hook back into the first stitch one round below. Yarn over and pull up a long loop, stretching it to the height required for the current round. [2 loops on hook]. Working over the next stitch, insert the hook into the next stitch 2 rounds below (in this case, ROUND 1). Yarn over and pull up another long loop, stretching it to the height required for the current round. [3 loops on hook]. Yarn over and pull through all 3 loops. The first long single crochet 2 together (long sc2tog) is made. Skip the unworked stitch behind the long sc2tog just made, and work 1 single crochet in each of the next 2 stitches. Work another long sc2tog (as in the previous steps). Continue to repeat the pattern all the way around until 2 stitches remain. Work 1 single crochet into each of the last 2 stitches. Work one more long sc2tog, working the second leg into the same stitch as the very first single crochet of the round.
4th Round
Skip the stitch behind the long sc2tog just made. Work 1 single crochet in each of the next 2 stitches. Use a stitch marker to mark the first stitch of the round. Repeat [long sc2tog, 2 single crochets] all the way around, ending the round as per the 3rd round.
Repeating the Pattern
Repeat the 4th round.