I learnt everything I know from Mac. Be aware that a nice wax job can be annoying to maintain though. Use a round wax type - e.g. Sex Wax - run it down each side of the board using the edge of the wax on an angle - following the edge of the rail. Then cross hatch it in. Make sure you are slightly rotating the wax in your hand as you move it across the board. For best results use a nice hard wax for your base layer then when you are happy with it apply a softer stickier layer as the top coat. Make sure you concentrate whilst doing it and get the cross hatches even - here is my first attempt - learnt a few lessons along the way!
The golden rule is to make sure your board always goes into your board cover the same way. You can also use a coloured wax - not my cup of tea - I am old fashioned and like to stick with white. One of the fellas at the beach up here is always changing his wax job - using different colours on a white Mal - sometimes it looks pretty cool - other times not - just saying