I do 3 lots of 3 of heavy braking then drive till cool about 5 miles, I find getting them over hot can damage the pad leaving deposits on the disc. On the AP website I believe is a useful guide on bedding in pads. It also depends on the pads. If they are Brembo boxed and from a retailer, you may kill them altogether. The above usually applies to competition or fast road pads. Road pads especially cheap ones are best braked gently for the first 200 miles, so the cardboard does not disintegrate.