Use user-centered design principles.  Find out what your users want to do when they get to your guide and make it as easy for them to do that as possible.

A useful tool is a user story.  A user story is developed by thinking about your users, identifying who they are, and identifying what it is that they want to accomplish.  User stories are very simple sentences that follow a pattern such as

I am a _______________ and I want to _______________ so that I can _______________. 

An example is I am an undergraduate student, and I want to find out how to cite my sources so I can write my paper correctly. 

Once you know what your users want to do, put the things that will help them do it at the top of the page.  Make it easy for them to do those things.

Wherever and whenever possible, reuse boxes and assets that have been created by others.  If you don’t have to put in the work to recreate it, don’t!  Reusing assets makes guides easier to maintain by keeping information that can change in one place. You will be able to apply your own descriptions to a re-used asset so you can tailor what you want the patron to know about that resource.