Disgruntled Hobbit
Adventurer
In terms of tools, I've also come across the "Stoplight System" which is the X-card with nuance
You have cards or something with green, yellow, and red circles on them. If things are going good and you want them to continue or get more intense, tap green. If you need to stop, tap red. If you want things to maintain or slow down but not stop, tap yellow
This is a useful system because it doesn't just allow the players to halt the action, but allows them to push for more intensity by tapping green.
This could easily be tweaked into using had signals: thumbs up, thumbs down, thumbs sideways. Or a so-so hand jiggle for uncertainty and to prompt the DM to inquire more or continue but check in again often.
You have cards or something with green, yellow, and red circles on them. If things are going good and you want them to continue or get more intense, tap green. If you need to stop, tap red. If you want things to maintain or slow down but not stop, tap yellow
This is a useful system because it doesn't just allow the players to halt the action, but allows them to push for more intensity by tapping green.
This could easily be tweaked into using had signals: thumbs up, thumbs down, thumbs sideways. Or a so-so hand jiggle for uncertainty and to prompt the DM to inquire more or continue but check in again often.