Once you have your partner on the phone, take things at a speed you're both comfortable with. There's no "correct" way to have phone sex.  If it helps you relax, spend a few minutes chatting before you get started... just don't let yourselves get distracted from your sexy goal. A low, soft tone of voice or heavy breathing can help set the mood, but don't force it if doing so is unnatural for you: speaking and breathing comfortably in your normal tone of voice will be sexier than an awkwardly forced attempt at sounding sexy. Getting started is possibly the hardest part, especially if it's your first time! Pick a topic that's easy for you to bring up, but which has the potential to spiral into steamier territory. Examples:   How much you miss them, or wish they were with you What you would like to do if they were with you What you're wearing and how you look in it What you're doing How you're feeling Ask your partner to describe any of the above to you Once you have the ball rolling and you're feeling comfortable, try getting bolder with your descriptions, or bring up new, sexier topics. A good approach is to describe, or ask your partner to describe, the following three things:   What you're doing: Describe how you look and the way you're touching yourself. Be as coy or as raunchy as you like!  Ask for "advice" -- for example, "should I start playing with my underwear?" Tell them what you'd like them to do, if they're willing. Don't feel bad if you're not comfortable with touching yourself -- you can still let them know that you're enjoying simply listening to them.    What you're imagining: This could be, for example, what you'd like to be doing with your partner, a moment from great sex the two of you have had in the past, or a mental image of what they're describing to you.  You might want to start out slow: begin with tame descriptions like "first, I'd stroke your hair" or "I really like the way your chest looks in a T-shirt", before moving on to steamier things like "then I'd kiss your neck" or "remember...

TL;DR in Vietnamese:
Bắt đầu cuộc gọi. Bàn về chủ đề thường ngày để chuyển sang cuộc nói chuyện gợi tình một cách tự nhiên nhất. Chuyển sang chủ đề chính. Tự sướng và lên đỉnh (tùy chọn). Kết thúc cuộc gọi.