Hiding. Make a Dexterity (Stealth) check when you attempt to conceal yourself from enemies, slink past guards, or sneak up on someone without being seen or heard.
If you do this during combat, then you also have to take the Hide action.
Passive Detection. A creature may notice you even if when not searching. Your Dexterity (Stealth) check is compared with the creature's passive Wisdom (Perception) score.
The GM decides when circumstances are appropriate for hiding.
You are more difficult to find in lightly or heavily obscured areas.
Certain armor may hinder your ability to be stealthy.
See the Unseen Attackers and Targets rule.