A method for using an insertion instrument to insert a cup into an acetabulum. The method includes inserting a convex outer surface of the instrument into an inner surface of the cup. The entire convex outer surface is made of a resilient material. A piston is activated in order to decrease pressure within a sealed cavity of the instrument, which causes the convex outer surface of the instrument to engage the inner surface of the cup. The instrument and cup are inserted into place in the acetabulum. The piston is de-activated in order to increase pressure within the sealed cavity, causing the convex outer surface of the instrument to disengage the inner surface of the cup.