Having documentation for your SaaS is essential. I know it probably isn't the highest item on your list, but if you intend on providing a self service SaaS, you will need great product documentation.
Maybe you've already written and published documentation. That's great! Still, there is always more to learn, and more that could be done to improve the support for your customers. For example, learning that documentation needs to serve different purposes, depending on the needs of the user.
Let's take a moment to drill down, and really focus on what great product documentation looks like for end user's.
Type of documentation
Knowing who you're writing for is extremely important. The main types of documentations; tutorials, how-to guides, explanation, and technical reference generally cater to specific types of users.
The reason I say generally, is that they all overlap to a certain degree. So, depending on your particular product, your SaaS product documentation could(and should) contain multiple types.
However, they should be separated into individual areas to prevent confusion, and better serve the needs of the user. This is one of those things that tripped me up. So much so that, I've had to do a major overhaul of our documentation. Luckily snazzyDocs made that pretty easy and painless. ;)
A common trap that I fell into myself, is creating content without much forethought as to where everything would eventually belong. It made sense (in the beginning) to sort content by topic. But over time, and as the documentation become more thorough, mere topics with subsections as my only way to organize was nowhere near adequate. Not just for users trying to use the documentation, but also for my own sanity as well.
The categories, consistency, and hierarchies you choose should be deliberate, and created with the learning process in mind. This alone can increase learning success, and makes it incredibly easy for you to write and maintain your SaaS product documentation.
Associate related topics
As mentioned earlier, the lines between the different types of documentation can become blurred when you factor in user journey, and where they are in that journey. For example, if you consider the needs of a brand new user, getting started tutorials are much more relevant and valuable. Whereas a more seasoned user would need an advanced how-to guide, or technical reference.
Remember though, both users at each end of the spectrum are, in fact, learning about the same topic. This is a perfect chance to segue to a related and obvious next step. Linking from the end of one difficulty level to the next is a perfect way to ease customers into the information they are actually ready to handle.
Users don't always enter at the start of your pre-planned flow either. Give them an option to "Go back" to the previous step or start at the beginning.
You know the saying.. "An image is worth a thousand words". Using images can do wonders for making, big picture concepts or complicated steps easier to understand. It breaks up the text on the page and helps prevent cognitive overload.
Experiment with concise annotations or big red arrows in your SaaS product documentation to bring attention to a specific element in the image.
However, using images does make updates and revisions a bit trickier than written documentation. As any changes or iterations you make with your product will need to be similarly reflected in your documentation.
Amend and improve
As you iterate, change or add features to your product, you will need to update your documentation.
Your documentation should be completely up to date with the latest version of your product. Provide documentation for older versions of your product that customers are still using via semantic versioning (eg. 1.0, 2.0).
Just like your product, SaaS product documentation is ever changing, and as such, ongoing revisions and editing should be a part of your normal process. Use feedback and customer support interactions as learning opportunities to guide further improvements.
Looking at the big picture, remember that your SaaS product documentation may indeed serve many purposes for you. But for the user currently using it, it serves one. Make it easy for a user to hit the ground running by clearly indicating specific areas. This structure affords them choice, and grants you ease of maintainability.