Just follow his basic technique and end up with a painting you would be proud to hang on your wall. Work around the canvas from all angles, don't paint with a brush, and let the paint hit the canvas with expression.
Don't be afraid to make a bit of a mess or get paint on you. This is an expression of yourself, so don't let a few paint drips hold you back.
'Action painting' requires you to have the canvas on the ground so that you can work at it from all sides and angles.
This is also a technique with no room for formal brushes; get creative and use spoons, whisks, paint stirrers, and anything else you can find around.
I would recommend practicing with your tools to see the effects they make and what works better for you. After you get a good feel for controlling the paint, then its time to attack the canvas!
You can never go wrong with primary colors. I used black, white, red, yellow, blue and gray. I found all the paints in the discounted mis-tinted area of house paints in Walmart costing around $25. Feel free to experiment with your own choice in colors.
If you don't like how your painting is turning out, just keep working the canvas and creating more layers. Its hard to overwork it and you'll be amazed at how well the effects work together and make you feel like a professional artist! It can be hard to know when to stop, that's mostly up to the artist in you to decide.
I ended up having more of a loose and active style while my brother ended up focusing more on layering thin ribbons of paint. Both turned out wonderful, so don't be afraid of what you end up with.
Go wild and give it a try, its a great way to let loose and have some fun while creating your own modern art.