Make a slip knot
Chain 2
Work 2 single crochet into the second chain from the hook
Chain 1 and turn
Work 1 single crochet into the first stitch
Work 2 single crochet into the last stitch
Chain 1 and turn
Work 1 single crochet in each stitch until the last stitch
Work 2 single crochet into the last stitch
Repeat the last two steps on each row to increase one stitch at the end
Continue until the triangle reaches the desired size
Fasten off and weave in ends