Two things to know about this square.
1 if you are a tight knitter use a 1/2 a size bigger needles than stated
2 at the beginning of row 1 avoid pulling your yarn too tight
ABBREVIATIONS - slwyif - slip the next stitch from your left to right needle holding the yarn at the front of your work. As you are purling this row you will notice your yarn is already at the front.
ARAN WEIGHT YARN AND 5mm needles
CAST ON 21 stitches
DOUBLE KNITTING and 4mm needles
CAST ON 23 stitches
Row 1 *p1.slwyif* repeat *-* until last stitch, p1
Row 2 - k1,*p1,k1* repeat *-* until the end of the row
Work rows 1 - 2 until your work measures 4" cast off on row 2