How to gain a child's trust?

It's simple! Say one thing and do another:

• Say "Man, I'm leaving" and don't leave.
• Say "Agne, I'm grateful" and browse your phone at the same time.
• Say "It's really important that you get good grades in school" and then don't help me study because, well, face it, does it matter to you? Does that even matter to you man??
• Say "I told you not to swear, bro!".
• Say "If you don't tidy up your room, you won't get candy" and then give the candy anyway, because the little prince let go of the cuckoo.
• Say "No" and pretend to be "Yes".
• Say "Yes" and then break your promises and say "No way".

Then the child will trust you, he will love you, he will grow up to be a healthy, full-fledged person.

(Of course I say this sarcastically.)