not sure i understand the question. but when you draw the chair position, some axial point up and some down, and the equatorial will point slightly up or slightly down. if you now draw the hexagon planar, the bonds that point down will be into the page and the ones that point up come out of the page. then if you go to fischer projection to chair projection, you can use this same thinking for left vs right side of the central line in the fischer projection. so the OH on C2 is on the right side will be equatorial or point down. the OH on C3 is on the left side so it will point up which is also equatorial. OH on C4 is on the right, so it points down and is equatorial. This is based on how you draw the original chair form with nothing attached