Wicked easy. You use #3 first this is where the majority of the work is done so take you time here but you apply it and use a cloth (I use a cordless drill and buff wheel) and work you way over the whole lens. Then wipe away any access and use #2 in circles with a lint free cloth. Repeat #3 and #2 until satisfied and then finish with the #1 polish.
Took me about 45mins this morning