Phone flirting relies heavily on your tone of voice, so make it sweet, deep and sexy. Don't go overboard trying to emulate a deep voice if yours is not, but take your natural voice down an octave. Keep your voice playful, fun and inviting. Make sure to kick off the phone flirting right from the moment you say "Hello" rather than trying to switch into flirting mode in the middle of a conversation. Better yet, instead of saying "Hello," greet the object of your flirtation with a "Hiya, sexy," or "What's up, kitten."
Even though the person on the other end of the line cannot see your body language, it can still be used to your advantage. Your tone of voice tends to match your mannerisms; people can usually tell if a person is smiling or frowning, even if they are on the phone. Sit casually with your arms open, not crossed across your body which closes you down. Make yourself fully comfortable and relaxed tilting your body back and leaving your feet uncrossed. Also imagine you are seated across from the person, looking into his or her eyes while you're speaking. The intimacy will come across. You can also look into a mirror and check your facial expression - be sure you have a smile on your face.
The words you speak can make or break phone flirting. Even if your tone and mannerisms are full of flirtation, you can wreck it all by starting to discuss controversial, boring or mundane topics. You can't really flirt successfully if you are arguing about politics. Instead, keep the conversation light and airy, dropping key phrases and subtle hints on how much you adore the other person or want to get to know them better. For instance, if you're talking about your day, you can throw in something as simple as, "Of course it all would have been much more fun if you were there." Be careful not to turn phone flirting into obscenities.