From personal experience we have found Graftobian spirit gum to be the best adhesive to hold nipple pasties firmly in place. It's the brand favoured by tassel-twirling burlesque performers, also used in theatre to stick pretty much anything to the skin; body jewels, fake hair, etc...

Apply the alcohol based spirit gum to the backing of the nipple pasties (especially at the edges) using the brush applicator included, then lightly tap the gum repeatedly with a clean finger until it becomes very tacky and apply.