When we review internal policies for a client, we usually find two kinds: the ones copied from another company years ago, and the ones written after something went wrong. Neither kind tends to be read.
Write for the person doing the work
A policy is an instruction. If an employee cannot tell, after one reading, what they should do differently on Monday morning, it needs rewriting.
Keep the reason next to the rule
People follow rules they understand. One sentence explaining why the rule exists does more than a paragraph of legal language.
Give every policy an owner and a review date
Someone must be responsible for keeping each policy current. A review date on the front page makes it obvious when a document has been forgotten.
Fewer, shorter documents
Ten clear policies that people know are better than forty that sit on a shared drive. If two documents cover the same ground, merge them.
