Say something like, "It's always so fun to talk to you," or "I always have the best time talking to you." Though she may get the vibe that you really like spending time with her, it may be better to just come right out and say it. Don't be afraid of telling her how you really feel. She'll really appreciate it and she'll be charmed by your smooth moves. Of course, make sure you actually are having a great time before you tell her that you always have a great time when you hang out with her! Develop some code words between each other. Use them around other people and laugh secretly as if you're having a private joke. This is a great way to make the girl feel like you're sweet on her. If you didn't like her, then you wouldn't share a private language, would you? Don't be too obvious about it, but if you can find a way to make the girl laugh or smile when you're alone or around others, that's definitely a way of sweet talking her. If you're at the "I love you" stage in your relationship, then make sure you let her know how you really feel. Don't just say it once every blue moon; if you love her, tell her every day, multiple times a day, without overwhelming her. And if you're dating or hanging out a lot, always remind her that you really like her. You can do this without smothering her and let her know that you really do care for her. Find a way to naturally slip it into the conversation. Don't just say "I really like you" or "I love you" when you need her to do something for you or to forgive you. Make it feel spontaneous. Making a girl laugh is key to sweet talking her. You don't have to be the world's greatest comedian to bring a genuine smile to her face. Don't be afraid to be a little bit corny or silly or just to say something a little bit random. As long as she doesn't feel like you're trying too hard, she'll appreciate the effort. You can tease her a bit, or even make fun of yourself a bit, as long as you're not being too self-deprecating. Remember that when you're sweet talking a girl, you want to keep things light, not talk about how your life has lost all meaning since your grandfather died. Make her feel light and airy and laugh as much as possible -- you can do the serious stuff later. If you tried a joke and fell flat, just saying something like, "You can't win them all," or just laugh at yourself a bit. There's no need to look crushed or to make things awkward. In fact, soon enough, you can both be laughing at your failed attempt. Take a minute to acknowledge something nice the girl has done for you. You can say, "Thanks for our conversation. It's definitely made my day," or "Thank so much for helping out last week. I couldn't have passed that test without you." Let her know that you appreciate what she does for you and that you're aware of how much she means to you. This will make her feel like she's an important part of your life and that you really care for her. You don't have to overdo it. If it's just something small, just say, "Hey, thanks for getting me this coffee. I really need it." You don't have to act like she did something life-changing while acknowledging her actions in a positive way. If you really want to sweet talk a girl, then you have to let her know that she's not like any other girl you know. Make her feel unique, and mean it. Find something about her that isn't true about any other girl and tell her how you feel. If she knows that she stands out to you, she'll really be flattered and will be touched by your effort. Here are some ways to make her really feel unique: "I've never met a girl who is as comfortable with herself as you are." "You're so good at listening to people. It's an amazing skill." "You really know how to make people feel good about themselves. I don't know anyone else who can do that as well as you." "You're not like any other girl I've ever met." Another way to sweet talk a girl is to actually ask her how she feels about something. If you're doing all the smooth talking, going on and on about how much you like her or filling her with flattery, then she can get bored pretty fast. Instead, take the time to actually ask her what she thinks about certain subjects. This will let her know that you see her as more than just an object and that the things she says really matter to you. Here are some things you can ask her about: A mutual friend A band coming to town A new TV show Current events (as long as you don't get into a controversial conversation too early) What she thinks you should do in a certain situation Another way to sweet talk a girl is to actually show an interest in who she is. Let her see that she's more than just a cute girl and that you see her as an individual with her own dreams and desires. You don't have to pry too much to let her know you're really interested in who she is. Avoid the extra personal topics and stick to things she'll be comfortable talking about. Here are some things you can ask about: Her hobbies and interests Her passions Her friends Her family Her pets Her plans for the weekend This is completely simple, and completely effective. Sometimes all a girl (or anyone, really) wants to hear is, "How was your day?" Nothing can sound sweeter to someone who had a bad, or just an interesting day, and who wants to talk about it. She'll be touched that you actually care about how her day went, and if you sound like you really mean it, she'll say more than just "Good" or "Not too bad," and will begin to open up to you. To truly sweet talk a girl, you have to find a balance between flattering her and actually making her feel like you care. Listening can be just as important as talking, when it comes to making a girl feel special. All the flattery in the world won't work if you don't take the time to slow down, shut up, and really listen to what she has to say. Make eye contact, nod occasionally as you follow along, and don't interrupt her when she's trying to tell you something. Don't tell her you know exactly how she feels and don't say, "That was just how I felt this one time when" Let her see that you care about what she has to say, not what it has to do with you. Face it: a lot of guys are notoriously bad listeners. Make yourself stand out as someone who is just as interested in listening to a girl as he is in trying to impress her. And if you're a good listener, she will be impressed. It's important to remember what she tells you so you can bring it up later in the conversation. She'll feel really special if you can bring up some offhand comment she made two hours or two days ago.

Summary:
Let her know how much you like hanging out with her. Mention your inside jokes. Let her know how much you love/like her. Crack her up. Thank her. Tell her she's unique. Ask her opinion. Ask about her life. Ask how her day was. Listen to her.