1. Start with distance — it's a dial, not a gap
Begin with contact that has room in it — kissing without being fully pressed together, for example. Distance is the first pacing dial: closer and farther are moves you can make at any moment. These steps are an order for learning the dials, not a timeline to follow — and they're four worth learning first, not the only dials there are.
One thing to know: most initiation between partners is nonverbal, so a step back or a pause will be read as a signal. Pair the move with a word when you want to control what it says ('I want to stay right here').
If you're usually the one being carried along rather than the one escalating, the same dials work from your side — slowing things down is a move you're allowed to make, not just something done to you.