How do you guys prevent cheating?


No offense man but it's rare that any at our level is an actual cheater. Most computers can smoke guys at our level they'd be at least 1600+. But to answer your question there isn't much you can do its the Internet and Internet chess is protected under chess rules it's a free for all that is monitored the best it can by the admins

Chess.com bans cheaters. One easy way to tell is when their moves match an engine's moves.
They can't monitor everything instantly though. So if your opponent's moves match an engine you can help by reporting the player for cheating.

Where's that nose-picking icon?

You've been here for 7 yrs and you created a cheating thread under "general chess discussion"...?? They can't prevent it, but they can ban it from the site. https://www.chess.com/club/cheating-forum

Where's that nose-picking icon?
Oh crap I just knight forked some limped lizarded king and queen he is 900+ does that count?
Yes.

And you're going to talk smack to me? Please continue.....

Chess.com takes cheating very seriously:
https://www.chess.com/article/view/chess-com-fair-play-and-cheat-detection
https://support.chess.com/customer/en/portal/articles/1444879-fair-play-on-chess-com-what-you-need-to-know
Discussions of cheating, potential cheating or cheat detection are not allowed on the general forums. If you would like to have that discussion, join the following group.