This is a tricky one. While it is very true that different people are different and will respond differently to someone's feelings, there are a few baselines that will help you see if a girl really likes you or not. As the great Captain Awkward says, people who like you will act like they like you.
Obviously this stuff is subject to an immense and absurd degree of individual variation, and really, if you like someone, the only way to actually know her feelings for sure is to take a deep breath and ask her. Yes, this opens you up to the possibility of rejection, and it does mean you really need to figure out what you want from this person, but by doing that you’re a.) maximizing the chances for them to respond favourably and b.) ensuring that even if they say no, you can gracefully walk away from the situation knowing that you’ve behaved well and courageously.
So, bearing all that in mind, what indications might you be looking out for?
1.) She repeatedly and pointedly discusses her queerness with you
If every time you hang out – or fairly early in the conversation with an attractive new person at a party – the conversation repeatedly turns to being queer, what it means, how you experience it, how you came out, etc…then it’s worth considering it might be a hint. Bonus points for meeting each other’s eyes intensely and then looking away. If they’re really keen you’re aware you’re their gender of choice – and/or that you display any other physical characteristics they really like – you might be in there.
2.) She's always giving you pointed compliments
If the person in question frequently compliments you, on your physicality or your mind, it’s generally a good sign. Some people will be shy about it, some people will come straight out with ‘you’re really beautiful’ or ‘your eyes are gorgeous’ – different strokes, I guess. The clincher for me is often people dropping into the conversation how much they like redheads.
3.) She is supremely awkward in your presence
Research shows that I am a long way from the only person who gets tongue-tied, physically awkward and socially incompetent in the presence of women I find attractive. If I can’t say anything or I'm generally displaying zero visible social skills, the chances are I fancy someone in the vicinity. This sometimes extends as far as avoiding being alone or having direct conversations with someone, although these days I am an adult and if there is any chance that I could actually realistically build a relationship with somebody I do my best to deal with this. It’s mostly surmountable by developing a real friendship with somebody and having conversations, so if you manage to make it through the awkward stage and discover a bond it’s an unequivocally good sign. But for lots of people ‘becoming unable to form sentences or coherent thought’ is in itself a sign of attraction.
4.) She remembers little things you’ve said you liked
From your preferred type of cookie to your eccentric taste in music, your favorite color or you unexpected liking for a particular boardgame, if she makes an effort to remember little things and then share them with you, it can be a sign of significant interest. It could be anything from cooking your favorite foods when you come round to ‘just happening to find’ a book you’ve been after for ages. It’s the noticing and then caring enough to act on it. Of course, she might just be a nice person – possibly worth finding out if she bakes EVERYBODY cupcakes!
5.) She spends lots of time with you, even in group situations
If I’m at a party with lots of friends, although it’s quite standard to hang around with one person or group for an hour or so, I’m likely to want to go say hello to my other friends too after a while. If I’m utterly absorbed in one person, it’s probably a sign of sexual interest – or at least the kind of Right Yes You Are A Person I Want In My Life Now sense of security and attraction that often blurs with sexual attraction in my sapio-sexual consciousness. Obviously, there’s a disjunct between this and often prompted by how well I know the person in question. It’s really about the bond between you – if you’re aware of continually seeking out her company and sparking conversation off one another, there might be something worth investigating there.
6.) Good manners vs. romantic intentions
A lot of figuring out whether somebody’s into you or not has to do with figuring out what kind of person she is (and thus, whether or not she's actually suited to you and whether you like her or not.) There’s a fuzzy grey area between signaling being a friendly considerate person open to building a friendship with someone and romantic interest. The most effective way of navigating this with someone you’re into is probably to ask. (Exactly how to ask is probably a forthcoming article, so watch this space.) That said, if there are any significant differences between how someone treats you and how they treat other people, you should probably consider whether a) you’re being creepy in some way (I would hope not!) or b) they’re into you also. Communicate around this, and happy endings could be yours!
7.) She initiates touch (with good excuses)
This is a classic. Somebody who touches you frequently (more so than they do other people they know comparably well), particularly on the hand or leg or other relatively non-aggressive-but-still-affectionate-areas, might well be trying to respectfully signal romantic interest. They might not, of course, but especially in company with significant glances and/or verbal flirtation, it’s worth looking out for. This is a bit of a cultural flashpoint, alas – wider Western culture seems to have problems interpreting sexuality between women as 'real.' But by the same token, it is also sometimes much easier to express platonic affection for a female friend physically precisely because it is less likely to be interpreted as a come on. I suspect predominantly queer circles are a bit different here - certainly in my social environments people are generally more affectionate towards one another than in the ‘mainstream,' and there is less stigmatization of affection - but it’s because we are all politically conscious and consent culture-y and it comes with an extra layer of negotiated consent ('do we do hugs?') This is great, but it is also unusual. To get back to the point, a lot of the time touching means sexual interest or at least a level of emotional comfort which means it’s okay to ask!
8.) She communicates a lot
In this day and age it doesn’t matter if it’s texting or WhatsApp or Facebook or whatever – if somebody goes out of their way to maintain a conversation with you and a general low-key presence in your life, that’s a positive sign. Especially if it’s a flirtatious presence. We’re all so busy and so besieged with jobs and messages that who we choose to communicate with regularly is generally a fairly reliable (although definitely not infallible!) indicator of who we care about. If you’re on that list for somebody new or somebody who maintains an edge of flirtatious or engaging curiosity, that’s a significant thing.
9.) What kind of liking are we talking?
Someone who’s found an antique copy of your favorite childhood book and a chess set with characters from your favorite fantasy novel as a gift is…probably not just in it for a one-night stand. Someone you meet at a party who tells you you’re beautiful, keeps catching your eye from across the room and squeezes your hand significantly on the way past might well be. ‘Into you’ is a general concept, and it’s probably best to approach all relevant situations with an eye to where you stand and where they seem to be, uh, coming from.