1. Don't hog all the items. Your team has a much better chance of survival if you share the potions and capsules with them so they have items when needed most. Of course you don't need to let them have EVERYTHING, but don't hog everything either, ESPECIALLY health capsules. Those should be divided amongst who needs them most if health is lacking.
2. Ask your teammates and discuss as a TEAM before opening a Danger Room door. Those fights are much harder then what you would expect for the floor you're currently on and it's rude to force your team into that situation by opening the door without their knowledge, thereby wasting valuable energy and potentially getting into a battle you can't win. And even if you're all in agreement, consider your current items and equipment and assess whether you think you can survive it without expending energy on revives. The rewards are well worth the battle, but not if you have to keep spending energy to come back to life over and over.
3. Before going to the next floor, make sure every member of your party is carrying a mineral, preferably the biggest one you can get your hands on. Minerals are shared by the party so if everyone carries a mineral, everyone gets the mineral that another player was carrying when the level is completed.
4. Plan ahead for ambushes. When you come to a party button in an open area, odds are it's going to be a brawl. Charge your primary weapon/place your bombs where you know the enemies will spawn, and raise your shield before starting the battle, and if you have any capsules and need health, use them. Always be prepared.
5. Before going to the next level, ask if anyone is going to leave after this floor. If so, kindly ask them to drop their vitapod and any capsules/potions they might be carrying. You can't take them with you, but your teammates could sure benefit from an extra health capsule or two, or that poison vial you never got around to using.
6. NEVER assume anyone will pay your energy tabs for you. If someone does, say THANK YOU. If someone revives you with energy, say THANK YOU. It goes a long way to know that their generosity is appreciated.
And of course, don't waste your energy on stupid things like treasure doors and robots. Danger Rooms are worth the price of admission, but make sure you and your team are all in agreement before opening that door, else the energy might get wasted, and so might you.
Note: Energy revives are supposed to be a last resource, even if your intentions are good, reviving teammates with energy will cause the revive cost to skyrocket for when it's actually needed.