Just out of interest, I've found the pre-ground and actual nutmegs both have the same effects when it comes to physical stuff like lethargy, red-eye, cottonmouth etc. The actual nutmegs seem to be more potent for the psychological effects. Apparently this is to do with the oil, and the nutmegs do seem to be more oily when you grind them fresh as opposed to buying the pre-ground stuff, so this may have some merit.
By FAR the easiest way to ingest nutmeg is to get the actual nutmegs, and using a nutcracker (or hammer) break them up into swallowable size pieces. No bad taste whatsoever, and your stomach acids will do the rest of the work for you. Seeing as how you're waiting 6+ hours for it to kick in, not looking for a rush as fast as possible, it doesn't matter that it will take a little while for your stomach to break the pieces up and distribute it through the bloodstream. Just make sure the pieces aren't too sharp or too big.
Finally, I'd agree with some earlier posts and say that if you are going to do it, 15g is plenty for a first time; I've never done more than 20g and this is enough to feel the effects for 24+ hours after it kicks in.