Bring one leg up onto a table/bed/box, bringing knee toward wrist, foot toward hip
Slowly reach both arms out over the knee, bringing chest to knee
Breathe
Slowly walk your hands out over the shin, bringing chest down to shin
Breathe
Bring torso upright and turn torso away from knee toward foot
Slowly reach hands out over foot
Breathe
Bring torso upright and turn torso away from foot and over the knee
Breathe 

If your knee is killing you in this position
STOP
Some people are too stiff to even get into position for this stretch without the knee joint screaming, so if you can’t get that leg in position, fear not! There’s a modified version