Bobble-head?

Anyone have any ideas on how to hold a wiggling baby on a changing table while trying to close those snap poppers on their new clean outfit with one hand? It's important to say that babies under 4 months old can't sit up yet. It's also important to say that for some reason 95% of all clothes have snap poppers at the back of the neck which would be the most inaccessible place to put them.