When I had 10 orchids I fussed over them all day, checking them every couple of hours. Now that I have 100+ I really don't have time for all of them. It takes a whole afternoon just to water them all every week, and I'm so busy with other things. I still love my orchids, but I wish I had more time to inspect each one at least daily!
One of the best cultural practices that I can think of is to pick up your plants and visually inspect them. If you don't look you don't see and they can be riddled with scale or mealy bugs that hide in all of the obscure places but you will never see them from a distance.
A lot, and with a flashlight at night. Using a flashlight lets you see in tough spots, also I can see the holes my dog made new in the yard(almost broke my leg once)