There are usually a lot of cards in play in the Pathfinder Adventure Card Game. But you don't need to worry about doing what all of them say all the time. Generally, powers on cards are only active in certain situations.
• Cards in your hand: Powers on cards in your hand are active only when you choose to play them.
• Cards you examine: When you examine cards, only powers that say they happen when you examine the card are active.
• Banes you encounter: All of a bane's applicable powers are active while you encounter it.
• Boons you encounter: When you encounter a boon, the only powers that are active are ones that say they happen when you encounter it, if you acquire it, or if you fail to acquire it.
• Other cards you encounter: When you encounter a card that isn't a bane or a boon, the only powers that are active are ones that say they happen when you encounter it.
• Cards in the hourglass and hourglass discards: The only powers that are active on these cards are ones that say they happen when they are discarded from the hourglass or when that card is the hour.
• Locations: Most powers on locations are active only when characters are at that location, but a few location powers affect other situations.
• Other cards: Powers on cards on the table – including characters and displayed cards – are active whenever they are appropriate. Powers on cards in locations, in the vault, and in your discards, bury pile, deck, and recovery pile are not active.
Playing cards from your hand is optional. Active powers on all other cards are only optional if they say "you may" do something.