I've done a lot of couch surfing in my life, and I've recently started to host people myself. Between those two I've learned a bit about being a good houseguest in most homes.
Some of this may sound a little formal - when you're staying in someone's life, for over a night or two, it pays to be a little formal in deference to your hosts.
Most all of this stuff is about alleviating your burden - the best houseguests improve the place they stay without demanding too much attention from the provider.
- do dishes.
- even if they're not yours.
but especially if they are!
- even if it's not your mess.
but especially if it is!
- pay attention
- see where they put that bowl? put it back there yourself. see what utensil they use with their non-stick pan? use that utensil. do they leave the shower throttle up or down? pay attention - your hosts would probably like you to observe the same small rules around the house that they do.
- buy gas and groceries
- figure what you'd be paying in rent you're paying partially in supplies. if you can't afford financial support, think of other ways to compensate. and a promise to provide a floor someday may not be enough.
- replace what you use
- 'nuff said.
- gifts help
- especially if you can bring something exciting or rare from your home - liquors, spices and foodstuffs may go as far now as they did in the days of the spice trail. but take into consideration the nature of your hosts and don't expect gifts to compensate for everything else.
- offer to cook
- your regional specialties might be appreciated. sparing your hosts effort is the key here.
- leave art
- something nice to honour the spot you stayed. but non-permanent so they can ditch it if it's not their thing. you can probably tell.
- entertain yourself
- a place to live is nice, and so are omnipresent friends. don't demand a tourguide. learn when to leave.