Tell him what you are going to do to him sexually. Talk about a fantasy in crude terms. Tell him what you want him to do to you - ravish you, dominate you, etc.
If you're new to this, you can start by telling each other what various body parts are called. (For example, how many words can you think of for "breast" or "penis"?) If this is embarrassing, go ahead and laugh. After all, sex is supposed to be fun!
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