Play yourself for a fool. Actions or deeds which are in opposition to one's own self interests.
"Don't play yourself!" yelled Jamal as DeShawn went up for a slam dunk even though DeShawn is only 5'-4" and only has a 12" vertical.
Guy1: I'll have cereal
*pours milk in first, has no cereal*
DJ Khaled: Congratulations, you played yourself
To mess up terribly, made famous by DJ Khaled
Congratulations, you played yourself
To mess up badly... Also, the example (taken from an Among Us clip that I cannot link).
Impostor (when he finds out he got Impostor): Oh you guys are so dead!
Random Crewmate: Alright, we gettin' his ass out first.
Random Crewmate 3: Bro, you guys are so dumb... this is just a joke.
Impostor: I literally said this last game...
Random Crewmate 2: No he didn't.
Literally everyone: Get his ass out of here!
Me: Ya played yourself.
When you set yourself up to fail.
A little get steals candy and gets punished for it. Congratulations, you played yourself.
This phrase is used when you catch a person in an outright lie. Catch a person lying to you.
Me, "Don't play yourself, I know you took the last donut!"
Other guy caught taking the donut.... Lolololol