Sometimes like-flirting can border on psychological torture, so here's a simple guide to figuring out what it all means. Because over-analyzing another person's actions will always let you discern exactly how they feel and never make you go insane.
Was he the first to like it or not? If he was the first, it could means he likes you because he saw it immediately and liked it, but it could also means he doesn't care about coming off as weird for liking it first, which means he doesn't care about you at all. Even though you just saw him and just had a really great conversation with you. How could he be so fickle?
What it Means: She liked it, so it automatically means she must like you. But a lot of people liked this and she was one of many, it really could mean she's just being supportive like everyone else was. But she liked it the next day so it's the most recent like, so she wanted it to be noticed and had to go on your wall to see it. But it might also have just come up on her news feed because Facebook's algorithm is weird like that. But would it really come up on that much of a delay? And why doesn't Facebook let you know if someone's been creeping your profile?
What it Means: He is completely into you. He's up thinking about 3 am. It's completely clear that he wants you. Bad. Unless he's just a night owl and does all of his Facebooking at this time. Did he like anyone else's photos? Your friend Michelle's perhaps? It still might mean something? Wait, isn't Michelle in this photo with you??? So he must like Michelle and not you. But the photo does feature you more heavily, and really it's only Michelle's leg and not her face, so maybe?
What it Means: She's into you! Why else would she like that you're single? Unless she likes that you're single because it means you're not dating her? She liked it after midnight, which means she was probably out on a date with someone who's not you. But she still bothered to like it so there's a 75% chance it was a bad date and she'd rather date you? But she still most definitely, probably, possibly had this date at all, which means she wasn't looking to date you even if she might, maybe, hopefully like you, so...????
What it Means: This is a clear sign that he likes you. Except for the fact that you're with another guy in the photo. Except for the fact that Jason is clearly gay. Except for the fact that he might not actually come off as gay in this photo. Except for the fact that if you click on his profile you can see that he has a boyfriend. Except for the fact that your crush might not have obsessively gone through Jason's profile because he doesn't have a crush on you back and doesn't care if you have your arm around another guy. Except for the fact that you look cute in this photo and he took the time out to like it at all? Except for the fact that you're with another guy in this photo. Except for the fact that Jason is clearly gay. Except for the fact that he might not actually come off as gay in this photo....
What it Means: The foam art in your morning latte looks like it could be a leaf or a heart, but one thing is clear: he likes you. Because nobody - fucking nobody - actually likes foam art anymore.