Among Us was a pretty amazing game at the start, but it got dry pretty soon. The userbase has died out. But, if you still have a soft spot in your heart for the game but don't find it fun anymore, try out the proximity mod. It's one of the hundreds of mods that have been designed for the game. This mod takes away the utter silence between rounds and allows players to talk to folks near them. This opens up a lot more possibilities and makes the game way more fun.
Another really popular Among Us Mod is the Sheriff Mod. It really spices things up by giving the crewmates a defense mechanism against the imposter. You're no longer free food for the imposter. You have a sheriff who can fight back. The sheriff in the game has the same kill button as the imposter and can kill him if he gets close enough. However, if the player turns out to be a crewmate, the sheriff dies, and the crewmates are now short two people. It adds a pretty interesting dynamic to the game and definitely takes out the repetitiveness that people have started to experience with Among Us.
Faking tasks is something that pretty much every decent player knows how to do now. There's nothing particularly difficult about that. However, what most people don't do is keep an eye on the task progress bar while they fake a task. If you're faking tasks in close proximity to a crewmate, they might be watching you. If you step away from a task without the taskbar filling up, they will become suspicious of you. Wait for someone else to do a task. As soon as the progress bar goes up, leave the area. This will minimize the chances of your fake task being caught.
A lot of players make the mistake of talking too much when they're an imposter. Its human nature that forces a person to defend themselves, especially when they are guilty of the accusation against them. Which, in this context, is being an imposter. Try to keep your explanations to the point and concise, so you don't seem desperate to prove yourself right. Try-hards try to look for a difference in tone wherever they can to catch you off guard. Don't give them that difference.