With working out how often it needs to be done, the trick is to be honest with yourself and assess how much you use your car. If it cops all of the elements, lives outside and is driven every day, then you will only keep it looking its absolute best if it's waxed every second month. You could get away with every third month, but then it wouldn't be looking too sharp after a few years. Another plus for waxing the car regularly is that you don't have to cleanse every single time you apply the wax coating.
I do our more used cars' bonnets every time with both cleanser then wax, as they cop the most heat, bugs and grime. It's important to remember that if you let the wax deteriorate away too far, that you will need to re-cleanse it again with the Auto Body Cleanser, so the wax has a great surface to adhere to. Your wax will also last longer on the daily driven car if you wash it weekly with our Auto Body Gel/Nanolicioush Wash too.
You will need to re-wax more frequently in the hotter and usually wetter summer months, as the environment and heat does a good job at breaking down its protection.
If your car is garaged most of the time, then you could get away with two or three times per year. Some of our cars NEVER see the elements and are garaged out of direct sunlight in a cool dry area. They only need to be waxed once a year max.