Begin with a stitch on the hook.  If you are at the beginning of a row, chain 3.

Wrap the yarn around the hook from back to front, then insert the hook underneath both branches of the V of a stitch in the fabric or row.  Wrap the yarn around the hook again, then draw the yarn through the stitch. 

You know have three stitches on the hook. 

Wrap the yarn around the hook, then draw it through the two stitches closest to the end of the hook.  You now have two stitches on the hook:  one old stitch on the right and one brand new one on the left. 

Wrap the yarn around the hook once again and draw it through both stitches on the hook. Now there is only one stitch remaining.