As someone who has been in the modular world for a few years now, and hopes to have it as a continuing hobby for many more years to come, I'd love to learn more about what it takes to keep a system healthy and running without issue. What are some basic "how-to" steps that I can take to keep my modules running at their peak as long as possible? Apologies if I'm missing some basic info listed elsewhere or in an older thread.

Specifically:
* How long can I keep my rack on in a single session?
* Should there be a cool-down/rest period between power-on cycles?
* Is there a correct way to turn off a rack (i.e., turn any ongoing signals down, etc.)?
* What are the best ways to keep the electronics clean?
* Do I need to worry about ventilation or temperature inside the case?

I'd love to hear some thoughts from people with electrical knowledge and know-how. Thanks!