Ingratiate (verb)

1. To establish oneself in the favor of someone by deliberate efforts.
2. To win the goodwill or support of someone, usually by flattery or other means of persuasion.

Origin:

From french ingratiater, from latin ingratiare (to make grateful), from in- (not) + gratia (grace, favor).

Examples:

1. He ingratiated himself with his boss by doing extra work.
2. She ingratiated herself with her new classmates by bringing them snacks.
3. He ingratiated himself with the customer by offering them a free upgrade.
4. She ingratiated herself with the teacher by doing extra credit work.
5. He ingratiated himself with the group by buying them drinks.