One time at school I decided to randomly put a flower on my shrt from outside, then my friend started frantically saying "That's gay bro! Take it off now" and refusing to walk with me in public if i didnt take it off

Listening to music.

I was playing some music on my cassette player at school one day, but it wasn't rock'n'roll according to the renowned expert that was discussing the situation with me, therefore it was "gay".

I would recommend that anyone concerned with privacy either use a burner account or not answer these kinds of questions.

While statistically I'm sure there are many straight men here, doxxing and other forms of identification are enabled by combining different breadcrumbs of information.

Wear a kilt?

TBH I've never tried and nobody told me it was gay. But I'm a sweaty person and I would love to air out my crotch except for fear of social criticism.

Driving a red sedan

Listening to Frank Sinatra singing about women by a guy who used to play grab ass with men. They always find something to project their insecurity on to.

Use a tote bag

Using black eyeliner.