Turn your board off. Hold the button on the back of the display while turning on the battery. There are like 10 threads on this already. Not sure what you searched.
There’s also not a lot of space between the top of the boards and the top edge of the enclosure. So if you screw it in all the way down, the bottom of your deck may touch top of the board. When I moved my BMS to get it off of the display button, I kept it on top of the display, but just a cm over. I secured it with some velcro. Moving the BMS put it at a slight angle and along with the velcro it raised it to put enough pressure on my space cell enclosure to crack it. There was likely a slight defect on my space cell enclosure to begin with, but something to keep in mind when moving your BMS.