How do I knit, purl, knit, purl into all 4 stitches at once?

you put you r needle though the four stitches then make a knit stitch which you keep on the needle and bring teh yarn round to make a purl stitch in the same place back through the four stitches and repeat twice all in the same stitch it sounds difficult and you might want to knit a little looser than normal so that you dont get all tightly tied up