5 Top Rules of Index Construction

Here are the 5 top rules when you’re compiling a great index:

1) Always use lower case for your Index entries

Use “password” instead of “Password”, or “boat” instead of “Boat”.

EXCEPTION to the rule: all Proper Nouns should start with a capital letter. “Africa” instead of “africa”, or “Toyota” instead of “toyota”.

2) Always use singular case for your NOUN Index entries

Use “fuse” instead of “fuses”, or “capacitor” instead of “capacitors”.

3) In your Index, do not have more than 3 levels of nesting

The human mind starts losing track beyond 3 levels.
Easy-to-read Indexes do not have more than 3 levels of indentation.

4) Do not use verbs for Index entries

If possible, all your entries should be singular nouns.
If, for example, you’d like to point the reader to the page where “adding a network” is explained, do NOT create an index entry “network” UNDER “adding”.

Do it the other way around.
First create a top level entry “network”.
Then under that, as a sub-entry create “adding”.

Why?
Because most people do not search for “adding” as an abstract activity in itself but only in its relationship to another concrete object, like “network”. 
So the best practice is to anchor the verb “adding” to the noun “network” than the other way around.

5) If you use an acronym as an entry, always create a cross-reference to its expanded form and then give the corresponding page number at the open entry

For example, your entry for MPG should be “MPG, see miles per gallon”.
And then: “miles per gallon … page 17” (just an example).
Otherwise, you run the risk of confounding your readers by an unexplained acronym whose significance remains a mystery until the reader visits that page and does further research.

If, on the other hand, you explain the acronym’s meaning in the Index, the reader will be saved that research and will develop more trust both in your Index and your document.

May your life be like a well-written Index!