Preying on someone's emotions can be a way to manipulate someone. The manipulator may cause a great deal of stress or anxiety and then abruptly relieves that stress. After the tension is relieved, the person is vulnerable and less likely to make mindful or rational decisions. They may respond to various requests.
Also, providing the person with the incentive to do your bidding is another manipulation tactic. There may be a reward involved in exchange for compliance or, you can pressure the person to comply. Blackmail is another tactic, although, it is downright playing dirty. There may even be more subtle forms of blackmail that are less obvious.
There are a number of different techniques you can use to manipulate people. It’s hard to say which techniques are the most efficient because it generally depends on the person who is the target of your manipulation. For example, one technique called guilt-baiting, may be very successful on one person and not another because different people will react in different ways.
Other ways to manipulate people involve the silent treatment. With this technique, the manipulator gains a power advantage and uses it as leverage over another person, creating doubt and uncertainty. Perhaps the most common technique is called “home court advantage”. A manipulate person will insist on interacting with you in a place where they will feel ownership and control and they know you may feel less comfortable.