To cast on to this block try the knitted cast on method:

KNITTED CAST ON VIDEO

Edge:
Every RS row begins by slipping the first stitch (purlwise) with the yarn held in the back. Every WS row begins by slipping the first stitch (purlwise) with the yarn in the front. Please note, that this will not create a uniform slip stitch edge for this block. The photograph of this block clearly illustrates that this is not a uniform edge. If you like the look of a uniform slip stitch edge the pattern can easily be modified as follows: For all rows (RS and WS) slip the first stitch purlwise with the yarn in front, work 4-st pattern repeat to last st, knit the last st.