C.A.
Dear M.,
Gentle repetition... let him know by showing him that you can't and don't understand him if he won't use his words. He probably will throw a tantrum in the beginning but if you stay with it and learn how to hold yourself and rock through the phase (;) it helped me lol), it will get better.
Unfortunately it's like a power struggle that we have to take control of. Others have told me when I was going through it to give them a choice. The obvious what you want him to do and the less desirable what he doesn't want to do.
Eventually... Over time it will work out. It just takes time and patience. I do like the signing idea, I'm having my 3rd and I think I'll use that one this time and Oh yeah... he's only 13 months! hee hee ~ he's doing just what he should be learning how to communicate!
May the force b w/u (lol)
C