Time

By default, time in the game world flows similarly to that in the real world. But as with any story it might be helpful to squeeze in more detail for intense scenes—or sometimes do the opposite and summarize entire days or weeks in broad strokes.
  How time flows in the game world is ultimately governed by your narrator, but it’s ideal to adapt the time rate to the needs of the campaign. Fitting the right time flow to the right situation can make or break the experience for players. Outside of the default free flow, some structured time flows include rounds, phases, shifts, and days.
  Rounds. Combat and other moments of high-stakes action are narrated as encounters to make them easier to follow. Each encounter is divided into rounds, and each round represents about 6 seconds of the game world. During each round, normally the party gets a turn during which each protag can move and take one action; an enemy group or anyone working against the party also gets a turn. As rounds are intended to be tense, it can be beneficial for each creature to have its own turn. During most other parts of an adventure it’s usually more fun for all players to be able to act at the same time.
  Phases. A "phase" lasts about 10 minutes. Dividing time into phases can be useful tracking time when time is still important, but not every single action needs to be detailed. Exploration or preparation, for example. Perhaps to explore a wondrous mermaid castle before high tide washes it away, to prepare a town’s defense before a siege, or to navigate a dungeon before depleting resources run out.
  Shifts. Optionally, each day of long-distance travel is divided into six shifts: 3 day shifts and 3 night shifts. Traveling can expose you to extreme climates, deadly encounters, or other hazards. Camping for a shift can partially recuperate you if you have food, water, and shelter but it isn't as restorative as a downtime day.
  Days. During extensive periods, a rate of days can work best. Downtime normally takes an entire day, but is the most reliable way to completely recuperate from hard adventures. Downtime trading is a reliable way to sell loot and buy new gear.
  Weeks. Often campaigns increase in scope as they progress. By later levels it is entirely reasonable for protags to manage a business, a guild, or even an entire city. When dealing with such large-scale agencies it can be useful to use a rate of weeks. Weeks might be used by some supplemental rules, but core content doesn't assume adventures will be run at this scale.
  Even Longer. For campaigns of epic length it can be fun to go further. For example, each time your group meets up for an adventure, in the game-world your party might regroup after months or even years. In your world it might even be possible to travel through time.