Ha! Well, the simple answer is – you don't. As I've mentioned above, after many years of fumbling with various methods of dust-protection, I finally made the leap to 'bareback' in 2012. I decided to trust my gear's ability to handle it. As I only shoot with pro-level gear – an EOS 5D Markiii body and L-series prime lenses, exclusively – the dust isn't really that much of an issue. It would be a very different story if I used zoom lenses. They don't do so well out there!