This is the basic shoulderslide:

Step back,

step together and to the left side of the lady raising your left arm

carry on walking taking lady's right hand to your right shoulder,

turn 180^o anti-clockwise while the lady turns 180^o clockwise and as this happens lady slides her right hand down your right shoulder,

as your face again catch her right hand in your left hand, (you have changed places)

return lady 360^o anti-clockwise.