Matchstick

The Matchstick strategy is about using a little conversation to spark up the relationship, also enable you to be closer to the people whom you are not so close.

Another tactics, if you don't agree with your client's idea, can use small gestures such as slight shaking of head or mumbling of disagreement (but not to the extent of interruption or full attention). If you know that you are going to reject the proposal, then don't wait till the end of the whole presentation to reject, this will annoy the other party, thinking that since you're not interested, why listen like you're interested?!