I found a great article on ENWorld but I forgot to save a link. :( If anyone happens to find it or recognize it, please let me know so I can credit the original author. Below is my attempt to recreate the method from my memory, plus my own application and expansion of the concepts and ideas the method suggests.

Pentagon Method
1. Draw a pentagram. Each point is an encounter.
2. Circle one point. It’s a boss or mid-boss*
3. Draw a slash through one of your lines, between two points. It’s an obstacle**
4. Draw a dotted line between any two non-adjacent points. It’s a shortcut***
5. Decide at which point your characters start.

* This is simply an encounter that’s more difficult than the rest, which could be diabolical, deadly, full of awesome treasure, etc. It’s a good place to have a set-piece boss or mid-boss fight.
** The difficult obstacle could be anything from a locked door to a demon guardian to a hedge maze. Think of it as a way to allow the players an obvious choice for sequence breaking, if they’re into that.
*** The “shortcut” is another opportunity for your players to exercise sequence breaking because some players need to be able to feel like they have more control over what happens to their character. You don’t want the encounters to be too linear and you also don’t want to make things too complicated.

When I started designing White Cliff, I came up with a huge list of monsters and obstacles and locations that I thought were really interesting and wanted to include in the adventure. I culled most of the list until I came up with what I thought were the coolest, most evocative monsters, locations, and obstacles, and created a rough order in which to introduce them, along with a rudimentary story. I’ll explore the design of some of the early encounters in future articles.