Popcorn Stitch: 5dc into your stitch. Pull up the loop of the last dc and remove your hook. Place your hook into the top of the first dc made, then through the loop of the 5th dc that is hanging. Pull that loop through the first dc.
The sc at the beginning of each pop row helps keep the edges straight.
Foundation Chain
Chain an even number.
Pattern
Row 1:
sc in the 2nd ch from the hook and all the way across. You will end up with an odd number of stitches.
ch1 and turn.
Row 2:
sc in the base of the ch1 then do your first *pop in the next st. sc in the next st.
Continue to repeat * all the way across ending with a sc.