I also found a tutorial for these burp cloths on Sew Mama Sew. The burp cloth pattern that I've used in the past has ribbon sewn on the ends but I thought these were extra pretty with a strip of fabric sewn down the center. And look they complement the blanket!
One note on the burp cloths: I bought the Gerber organic cotton diapers and they were awful to work with. They got caught on the needle and snagged. I would recommend using the regular cotton ones instead.