1. Your wardrobe is at least 50% T-shirts.
Most of your outfits consist of jeans and a T-shirt, or a hoodie.
2. You've been told you "dress like a lesbian"
If wearing flannels and beanies makes me a lesbian, then I'm the biggest lumberjack beanie-wearing lesbian there is.
3. When you do actually dress up, everyone is shocked.
You've probably heard "Wow, you actually look like a girl today!" so many times. Or you might get a ton of compliments because nobody's used to you wearing much else besides jeans and a t-shirt.
4. The closest thing to dress shoes you own is Converse or Vans. Maybe combat boots.
"What do you mean I can't wear Vans at my prom/graduation/wedding/funeral??"
"How the hell does anyone walk in heels??"
5. You're obsessed with food.
And there's probably no way you'd order a salad on a date just to seem more like a "lady" and not the messy-eating food lover you probably are. Whoever you're dating can deal with it.
6. You have no idea how to do makeup/hair well. Or you're just too lazy.
You probably either suck at doing your makeup or hair, or you're just too lazy to do it half the time. The extra sleep in the morning is more appealing than having perfect hair or winged eyeliner anyway.
7. You swear constantly.
8. You probably don't carry a purse.
This can be kind of an issue because while you don't carry enough things to need a purse, it won't fit in the tiny pockets that women's jeans have, if your pants even have pockets at all. You're either forced to carry things in your hands all the time or carry a purse just for your phone, wallet, and keys. You see no point in carrying a purse 90% of the time.
9. You don't know how to flirt.
When you try to flirt it usually comes out as "uh, I like your face".