I did a one day course for a diploma and then went on to do the full NVQ, I'm sure with practice you can give a nice relaxing facial with a one day course BUT in order to know what you're doing and why you're doing it you do need to get the NVQ or a full qualification that includes health & safety, muscle structure, skin structure, lymphatic, circulation, contra indications, shall I go on...
Also with a one day course you may get insurance but you wont get a decent product!!
I think, if I remember correctly, if you go to a private co. with the NVQ you can do all the modules seperately, if thats the case you can get the proper qualification without doing the whole thing.
Carla x