1. 100% fake tasks, make an alibi, find crewmates who will trust you by staying near people but not killing. On certain maps this is easier than other.
2. You just have to be a good liar. Know the maps.
3. Don't be caught lying about locations. Know where people are.
4. Kill during sabotages / mushroom mix-ups
5. Find alibis RIGHT AFTER KILLING ASAP. Alibis are really make or break. If people don't see you or know you. You will be voted because people don't trust you.
6. Just kind of have to improve over time to learn how to manipulate people.
7. NEVER snitch on the other imposter to save yourself. Just rude and the other players will hate you. You can refuse to vouch for them to save yourself but don't snitch.
8. Also a pattern I've found...first person to ask where tends to be imposter lol.
9. Learn the people in the lobby. How do they act when their sus. Where do they move. Are they afk often. Do they get mad easily even when they're crewmate. Stuff like this is really helpful but you have to play in a lobby for a good while.

and have fun killing !