While a Player Character is Dying, at the beginning of the creature's turn, the creature rolls death saving throws.

Death saving throws are made at the START of the character’s turn. Unlike other saving throws, there is no bonus from ability modifiers to this roll.

Roll a d20. If the result is a 10 or higher, it counts as one success. If the result is less than 10, it counts as a failure. You want to get three successes to cling on to life and become stable. If you get three failures, your character dies. It doesn’t matter what order these successes or failures come in.

It is possible to have a critical success or a critical failure on your death saves.

On a roll of 1, you take TWO failures instead of the normal one.

If you roll a 20, you INSTANTLY recover with 1 hit point.

------Several gritty rules allow for more realistic bleed outs. Like rolling a 5 or lower results in a stack of Maimed (1).

Also another rule is all death saves are rolled in secret to prevent metagaming.