Ah yes the three main Abrahamic religions: lowercase t, that one ball in Toy Story, and 2 triangles

Not techniques I use personally, but different forms of manipulation that one could (but shouldn't) use. You should look out for:

1. Informing someone of a fact that is different than what the recipient actually experienced. If they question it, tell them they just forgot it. This works best on people who don't write stuff down (like a diary).
2. Giving someone a gift out of nowhere. To most people, this gives them the feeling that they owe you.
3. Helping someone frequently to the point where they start relying on you. (See previous point)

A few manipulation techniques that should not be used. If you see someone doing these things, assume they have an ulterior motive.

How long till they die. could be used in good and bad ways but I think knowing is better than being oblivious.