If you need to persuade a whole group of people, make sure that at least one person in that group will quickly agree with you. In that case persuading the others will be easier. So having a conversation with one person before confronting the whole group might be a good idea. This advice comes from an article on the management-issues.com website. Here are the rest of the tips:
1) Consistency
People want to be perceived as consistent and rational and thus try to present themselves in that way. So after giving their initial approval, they will tend to keep that agreement also during future interactions. Having once said yes to something, people like to stick to that position.
2) Power courtesy – and the advantage of being an expert
If the person you are talking to doesn’t want to offend you, or sees you as an expert in your field, they will try more to agree with your standpoint rather than oppose it.
3) Reciprocity
When someone disagrees with you, there are more options than starting an argument or providing reasons for your position (which may actually come very close to the previous option). Nor is there any need to be offended or just walk away. Instead, you can always deploy reciprocity.
Think about the people you want to persuade. Can you do something for them? You can also exaggerate your initial request so as to be in a position to make concessions later.
Remember: integrity matters
Some human tendencies can be used in order to persuade. They can also be used in order to manipulate. But beware: if you manipulate people into doing something that is not good for them, you might completely destroy the trust that exists between you. And when that happens, your position as a leader will be much more difficult.
-jk-