How do I regenerate my health?

Solution 1:

From the Wiki:

Using a Bandage, Medkit, or Red Stim Pack.
Sleeping in any Bed, tent or any object it is possible to sleep on.
Eating certain foods can temporary increase health regeneration.

For foods that heal, see this question.

Beds are easy to craft and you can find tents and sacrificial altars, both of which act like beds while exploring.

Personally I use sacrificial altar (while out of combat), seems to be one of the fastest beds to heal) and bandages (while in combat), because bandages are extremely easy to acquire once you gain the ability to travel to the galaxies far far away.

Solution 2:

Starbound doesn't have any passive health regeneration (at the beginning, at least), so you'll need to build some healing items. Early in the game, you have two at your disposal.

• a bandage can be made with 4 pieces of plant fibre and no other tools. Once used, it will recover some health for you fairly quickly, but not instantaneously. Bandages are single-use, so unless you establish a renewable source of fibre, you'll run out eventually.
• a wooden bed can be built at a crafting table. This requires a total of 15 logs, refined into planks. Resting in a bed will slowly recover health at no cost, but you won't be able to do anything else.

If you're lucky, you may find some red stimpacks in random containers. These are limited, but effective at recovering your HP.