If you don't want it to be too dirty just start off by saying how you are feeling (i.e. horny or "excited")and hint at what you want to happen. From his/her reply just respond depending on what they say and what you want to tell them or the direction you want to led the conversation. Really it is a case of just telling or hinting at what you want to happen in RL!:o)

Have fun!! :o)