Yarbish is a language, or way of speaking. Common Yarbish words include, "yarb" "boy" "jeah" "fuck" "shit" or any other profanity (many urban dictionary terms: such as "narb"). An appropriate way to speak Yarbish would be to use the dialect of the "Unforgivable" guy or the "Terrets" guy from YouTube. Speaking Yarbish is a good way to bullshit with friends and not give a fuck. (The key is to use unnecssary swearing).
"Aw, jeah boy! I gave her somethin' real nice!"
"I don't give a fuck!"
"Shut your bitch, faggot."
"Boy, if you don't start speakin' Yarbish, I'm gonna give you some NSR."
"Shit yeah!! I got another god damn narb!"