When the crochet instructions tell you to do a stitch "in the cluster", what does that mean exactly.?

I am working on a crochet project, and the instructions only tell me to do a dc in the first cluster (making the cluster part I understand), but I do not know where in the cluster they are talking about. Can anyone help? These instructions are just so hard to understand. Plus, I made the beginning chain the exact number it specifies, but it row 2 i ended up with 9 less clusters than it said I was supposed to have. Any ideas?