Your working crew is split, evenly, in to two shifts. One half will work jobs while the other half is “off duty” and will seek needs fulfillment. This means you need to consider half of your crew has about twelve hours to restock all of their needs.

Shift changes happen at two specific times in the day and your current shift is shown by the sun and moon at the bottom right of the screen. It's next to the clock and the pause/speed controls. You'll hear a whistle toot sound effect when the shifts change too.

If you are having a bad problem [and possibly not going to space today]: set an alert condition. Yellow cancels staff break time meaning you temporarily double your workforce.

• Crew will seek to fulfill a need once it reaches at least 75% and the bar turns yellow. Important note: they do not use a machine until the need is filled. They seem to take a fixed amount of time regardless of how depleted the need is.
  
  
• Each ~10 crew on board consumes ~0.15 food per hour.
  
• Crew takes about an hour and a half (1.5h) to finish eating at a table.
  
• Crew takes about an hour to take a shower.
  
• Crew sleeps for about 3 hours.
  
• Crew drinks from a soda machine for about ten minutes.
  
• Kitchen—crew takes 15 minutes to cook a meal.

You should be able to work out from this that a single bunk can optimally service four crew in a shift. You'll want to overbuild since crew don't show up at the exact right times to sleep and will wander off to do something else if the bed is taken.

I've also simplified the numbers after calculations so they are easier to keep in your head. This means they're slightly off the actual count, but you will need to overbuild to account for the crew's meandering anyhow.

Important note: the power facilities currently require power to work. If you upgrade to nuclear or fusion power source—and then your ship reaches zero power due to mismanagement—your ship is dead in the water and there is nothing you can do.

If your ship is almost dead in the water you can turn off the power switch various rooms to shut off all the equipment in there.

• Fuel burning generators produce 100 energy and consume biofuel so long as a crewman is sitting there playing solitaire at it.
  
• Fission generators produce 50 energy when unmanned, and 100 when a crewman is playing minecraft at it. I don't think these require a fuel source? But they require composite to build which makes them spendy.
  
• I haven't built a fusion yet.