When entering a dungeon, the first thing to realize is that they were generated rather than designed. Each dungeon starts off as a series of intersecting hallways with preset locations for the ladders up and down, and then doors and other obstacles are added randomly.
On each level you should always be aware where the up and down ladders are, because they don't move. On the first level you'll start in the northwest corner of the floor, and the ladder down will be near the south end of the next north-south hallway to the east. It's usually relatively easy to find this first ladder.
Each pair of dungeon floors features the same set of five enemies. On the first two floors, the enemies are fairly weak.
Thieves will steal your reserve
Weapons, which tends to be more annoying than effectual. You may want to sell off your extras, or invest in a lot of cheap
Daggers if you have
Weapons you want to keep in your inventory (such as
Ropes & Spikes). The monsters on
Dungeon Levels 1–2 are very little threat.