Aaron Peori
Rest in Peace
I'm gonna run my first 5e game in a couple of hours, this is my first time being GM and for two out of four players the first RPG they have ever played and none of us have ever played 5e.
We're going to using the starter set (Phandalvar), any suggestions on pitfalls to avoid and things to do?
There is a falling rubble trap in the first dungeon that doesn't really have any way for the players to spot or avoid it aside from just not walking through that corridor. Consider letting anyone with a Passive Perception of 15 or more notice that the path looks unsafe.
More generally:
Make certain that at least one PC has Spare The Dying or Proficiency with Heal checks. With those on hand you can feel free to knock out PCs with relative impunity since PCs can recharge back most of their HP after a short rest and all of it after a long rest.
Players should be strongly encouraged to take the flat HP per level since the amount given is actually above average for what they would roll.
There are no explicit rules for it, but allow players with Knowledge (Arcana, Religion or Nature) identify monsters and their resistances/immunities and vulnerabilities. A roll versus 10+CR should be good if you want to make them roll for it.
Encourage PCs to negotiate by allowing them to succeed quite often, and have the NPCs honor their agreements even when dealing with monsters. Give the PCs full XP for overcoming the encounter if they talk their way out of it. There are several encounters which would be very dangerous especially at low levels, allowing PCs to bribe, intimidate, fast talk or otherwise use diplomacy is worth more than fights to the death. Similarly, if the PCs decide to take prisoners don't make the bad guys constantly fight back. Let them interogate and decieve captured opponents into revealing more about future encounters.
Have thugs and goblins run away.
Never punish fun ideas. If the entire party seems to think a certain tactic or method or move is really cool, let it be cool. Give Inspiration away liberally and encourage PCs to spend it liberally as well.