Jeets, being ESLs, draw most of their English from the Internet, and if they're on the Farms they've likely pulled heavily from places like 4chan and will attempt to integrate the jargon of these sites to try to pass themselves off as legitimate posters. This could be overuse of common memes, but I've also noticed an overuse of vulgarity. I know this isn't exactly the place to police language, but jeets will use slurs or swearing in ways that don't square with the common prose of the website. "Faggots" as a suffix is a particularly common one (not "fags", mind you, specifically "faggots"; I've seen a number of jeets gravitate to the phrase "white faggots"). Similar idea with overuse of the word "nigger". Jeets hate blacks and will often integrate this into their slight digs at Westerners, being quick to call them "nigger lovers" and the like. General edgelording is common among jeet infiltrators.
General schizophrenic framing / incoherent worldview. That's to say that it can be odd to determine what the jeet-in-hiding is really proclaiming to believe. They'll do lip-service to anti-immigration talking points and may even use slurs like "curries", but will still deflect blame to whites / Jews / Chinese / globalists while simultaneously implying Indians will do society's needed dirty work. They dance between being ostensibly pro-white and calling you Cletus and reveling in ethnic replacement fantasies, and tend towards blackpilling others in an effort to share the misery inherit to being Indian.
VERY mild pushback on anti-jeet sentiment, attempting to pass the buck to the Global South broadly or saying that "poor white trash" are unhygienic or trashy too. Again, they are very tentative about this because they know it induces suspicion. Still, they will do so if they take particular offense to a given line of discussion. This trend of jeets likening others to themselves is well documented and doesn't need much more elaboration.
Indians are known to be preoccupied with rape and racemixing, that much is obvious. Like vulgarity, jokes about THE RAPED are common among legitimate users here, but jeets will integrate rape into their rhetoric in ways that aren't comedically loaded. As for racemixing, it doesn't even need to be "I FUCK YOUR SISTER BENCHOD", but be wary if they tend to wrap their rhetoric back to whites racemixing with nonwhites. It doesn't even need to be about mixing with jeets, as jeets see blacks as especially degrading for whites to mix with. Jeets know that they're genetic trash and revel in the idea of whites, and sometimes east Asians, being brought down to their level. Basically, if a poster comes across like a sex-obsessed pervert who has probably tried to molest a female family member, odds are it's a jeet.
General trolling behavior. Again, we all can appreciate a little trolling, but Indians will do lame bumass trolling that just amounts to posting their disjointed garbage for pages on end and giving snarky two word replies whenever anyone tells them to piss off. Their idea of being witty or shrewd is flinging shit everywhere and collecting trashcan reactions.
When jeets realize that their cover is likely blown, they'll suddenly go quiet for long periods, only posting every couple of page turns. They'll begin to say far less because they know that the more they say the more likely they'll be pegged as a jeet. It's a strong sign if a catty, chatty edgelord suddenly goes quiet after enough slapfighting. If their cover is compromised entirely, they'll lean into "send bobs" memes and pretend they were just LARPing as Indian the whole time and refuse to ever give it up no matter how much negative attention they're given.