1st row--2 single crochets in each stitch.
2nd row--2 single crochets in every other stitch.
3rd row--2 single crochets in every 3rd stitch.
4th row--2 single crochets in every 4th stitch.
As the rug gets larger this may have to be adjusted as it may get wavy.
It is a very forgiving item to make, particularly if it is loose.....I never go back.....just keep adjusting as you go and it will be fine in the end.
do you know how to make a square or oblong rug.......can you tell us the directions.