In order to do this you will need to draw a Lambert grid first using a pencil, a ruler and a north diagram. You need to pick up a magnetic direction on the field (that means the angle in between the magnetic north and the direction we want to follow). If you want to report this angle on a map using the Lambert grid, the reference will not be the magnetic north anymore but the Lambert pole. That’s why you shouldconvert your magnetic direction in a heading Suppose the magnetic direction you piked up is 249° and the angle between the Lambert pole and the magnetic north is 7° (same example as convert a magnetic direction in a heading. The heading is then 242°.

You need to put 242° in front of the mark on your compass :

Find the precise place where you are standing on the map and put the side of the compass on that spot. Make sure the rear lines of the dial are perpendicular to the lines of the grid, north up :

Draw the direction you want to follow with a pencil on the side of the compass : the mark is on it.