This video crochet tutorial will help you learn how to crochet the dew drop stitch.
Foundation Chain: Multiples of 3 + 1
Prep Row: 3 dc in the 5th chain from hook, *skip next 2 ch, 3 dc in next ch, rep from * across to within last 2 ch, skip next ch, 1 dc in last ch, turn
Row 1: Ch 4 (counts as dc, ch 1), *dc3tog in next 3 dc, ch 2, rep from * across to within last 4 sts, dc3tog in next 3 dc, 1 dc in top of turning ch, turn
Row 2: Ch 3 (counts as first dc), *3 dc in op of next cluster, rep from * across, 1 dc in 3rd ch of turning ch, turn
Repeat row 1 & 2 until you have reached your desired length.
After a few repeats your pattern should look like this: