1.People feel obliged to give back to others when they have received a service or a gift first.
Now the gift can be anything but this works well with people who would genuinely need it.Don't force gifts on to people that have no desire for it offer it. This works very well when you have no attachment in giving that gift or service. Whenever you want to work with someone to gain their interest in working with you. Offer something to them of interest to persuade them into working with you. Would you work with someone you don't know about? Most likely no. So offering your time to get to know one and other. Giving a gift or a service will build the relationship and build trust.
2. People want more of things they can have less of, exclusivity holds value.
Now I want you to imagine having a jar full of cookies. Time after time you've gone back and forth eating these cookies along with other people. You realize you only half one cookie left. So instead of eating it you save it for a day you'd like to eat a cookie. You come back the next day and the cookie is gone! This makes you mad as ever. When the jar of cookies was full you didn't mind if some were eaten but as soon as it was down to one cookie. It became valuable to you more than having a whole jar of cookies. When things become scare the value of it goes up tremendously. If you ever seen ads online about “limited supply” “one time only” this is triggering the scarcity in people to see value in a product or service.
3. People are more easily persuaded by people of authority and credibility.
This is a very common thing that people usually sway to. For instance say you see a person in a lab coat with a planner in his hand in a hospital. Automatically you start to believe that person must know a lot about being a doctor and is a doctor. This also applies to any person that is respected by many other people in their field. The sense of authority and a groups approval from an academy or an industry creates a sense of authority. Authority can be built on rules or special places. For example you start a fight in a club or a bar they'll throw you out. Because one the group has established an authority for the place and the reputation of the place does not allow that behavior.
4. People like to be consistent with things they have previously said or done.
One of the things you can do to get people to own up to or comply better is to have them participate in something were they made the decision on their own accord. But have the proof or records to enforce it. Real easy example is contracts or even having a group of people witness what happen or a recording. People want other people to like them. Therefore being consistent with their actions builds that belief of acceptance.
5. People prefer to say yes to those that they like who share the same views and values of themselves.
We like our friends and we have a level of trust with what they would recommend for us. A good amount of people will accept a stranger as a friend if they were properly introduced by a friend they trust. Also stuff your collective would like you'd be more likely to accept or try out because you trust the collectives acceptance to that stuff.