The bold letters in the column labels (top edge) and the row labels (left edge) are used as initials of adjectives, verbs and nouns to inspire ideas for dungeon dressing; if you can't think of a word that begins with one of the initials, the index number behind the letters can be used to look up words from the central lists.
Row labels have a variety modifier in the upper left corner of each box (acid, dry, twisted, quivering, etc.) These are meant as descriptive modifiers for geography, but can be used to describe other items as well. In the lower left corner of each box are two other labels: the first line is a creature category that defines generic monster forms, while the second line is a type of territory (defined as how nearby people interpret or use a geographical area.) Note that both creatures and territories can be of the "enchanted" type, so only one label is printed here.
Column labels have an action type printed vertically in the lower right corner of each box (break, empty, throw, etc.) These can provide general guidelines for what an object does or a monster is doing; they can be replaced with conceptually similar actions or any action beginning with one of the initials, if the listed verb makes no sense in the context.
The column labels across the bottom edge are printed vertically in the upper right corner of each box. The first word is a color, the second is a material category; either can be used as descriptive modifiers for various kinds of dungeon dressing. The bottom edge also has index numbers, which can be used to emulate a d6-1 dice roll; if you read the zero as a six, it becomes a standard d6 result of 1 to 6. This can be read as a column index for the central lists.
The row labels across the right edge have an equipment category printed in the upper left corner of each box, instead of a variety modifier. This can used as a simpler, broader alternative to the object lists in the center. "Armor" is assumed to be any defensive equipment, so it can be broadened to fur parkas or gas masks, if these seem appropriate; "Travel" equipment includes climbing or riding gear as well as vehicles; "Light and Senses" covers not just torches and lamps, but anything that improves detection, such as a stethoscope. The lower right corner is labeled with the six standard abilities, which can be used to indicate what an NPC excels at, what ability is penalized by a poison or disease, or many other uses.