How do I break in a tube amplifier?

Ditto to Wolf garcia's comments!BTW I have had less problems with tube gear than solid state! Once in a blue moon you might have to replace a tube but that's about it. Enjoy and don't worry!

Considering I can't leave the tube amp on without speakers connected and I only have one pair of speakers that need to be connected to my home theater system the majority of the time it'll be hard to leave it on for more than a few hours at a time. Especially, considering I can't leave it unattended while it's on.

I'm starting to appreciate solid state more all the time :-)

Mcjelo- Wolf is right. People are making this much too complicated. Because of the potential to damage the output transformers, the general rule of thumb (not necessarily applies to every design but being conservative never hurts) to to always make sure that there is a load (read speakers) connected to a tube amp before you turn it on. Of course, that also means that you should turn the amp off before disconnecting the speakers. Not leaving it on while you are away is a fire safety issue, but similar to leaving the iron or stove on when you leave the house, it's most likely not gonna burn the house down.

Otherwise, the rest of it is, IMO, hokum, at least as far as being "bad" for the equipment. Tube gear warms up more quickly than most ss gear (Class A ss excluded). If you want to wait 1/2 before listening, that's your call but w your kids or my schedule, that most likely ain't gonna happen and it's nothing to sweat over. As far as switching it off and on frequently, unless you use expensive NOS tubes, there is no reason to be overly concerned about "thermal cycling" If your amp has a current or inrush limiter or soft start circuit, that concern is effectively eliminated. As far as other issues, some designs push the tubes harder than others, which IMO, is much more likely to have a real effect on tube life than how long you leave it on or off, or break-in. As Wolf said, just fire the sucker up and enjoy!!!

Why would you leave it on? Turn the amp on when you want to use it!

I do think it's important to turn it on before listening to it, although leaving it off all the time does make the tubes last longer.