Green Light

Safeties of the green, yellow, red light variety are fairly common. Red means the play has to stop so you can discuss or do aftercare. Yellow means go slow, discuss, maybe bring the subject out of trance and talk about it.

Green means "yes, more like that, please"

Using the green safety normalizes using the other two and also helps your top know what to drill down on and focus on. What if it triggered you as well, and helped you to use all of your information conveyance: knowing you can always say any of those colors when they apply no matter how deep you are.