Row 1: ([dc, ch 1] 3times, dc) in 6th ch from hook (StarSt made), *sk next 3 ch, StarSt in next ch; repeat from * to last 3 ch, sk nest 2 ch, dc in last ch, turn--4 StarSt.
Okay, so you've chained 21. From your crochet hook, you count over six chains (don't count the loop around your hook, though). In this 6th chain, you will do the ([dc, ch 1] 3times, dc). This pattern, the ([dc, ch 1] 3times, dc), is the StarSt.
Next, you skip three chains and do another StarSt in the fourth chain. You will continue inserting the StarSt pattern into every fourth chain after that until you get to the end of the row. Then you will skip 2 chains and double crochet in last chain.
Does that help?