Finding true top dead center

i just need a better understanding, so after i find true tdc, do i use the pointer after i moved it to true top dead center? Or after i check true tdc do i move to pointer back to factory tdc ? To make my adjustments off of ? Please help for a better understanding

The pointer you added and adjusted to true TDC is the one you'll be using for your cam events. Once it is set to true TDC, you don't move the pointer.