If you aren't sure exactly what to write about or include, you could create a status update on your various social media channels, blog, or newsletter if you have one.
Ask your followers what they'd like to know about the subject, what their biggest challenges are, and how they're currently approaching or trying to solve the problem.
This will not only help you refine your content and overall structure, but also validate what the market actually wants and needs.
Involving these people in the process will make them feel like VIPs and they'll be more willing to share something they've been a part of once it's published. It also gets the activity within the guide up so that other potential readers see that there's obviously something of worth inside the guide if so many people are involved.
This is also a great way of growing your following: