There’s not enough space in this box for my answer, so here is a watered-down version!
I think most organisaitons that haven’t got a SAM function previously manages their licenses poorly. Some organisations don’t even keep a record of all their entitlement records, which further adds to the time, challenge and complexity of your task.
First things first – do a complete sweep of your procurement tools, finance/AP teams and get everything you can for your top 5 vendors (if you know what they are, if not, use this data to define your top 5). Start looking at their existing models and licenses. Is what they have fit for purpose? Are there any glaring risks that you need to address ASAP? Any renewals due in the next few weeks that you know you’re going to be reactive rather than proactive on?
Start to paint the picture of what your estate looks like, and how your top 5 vendors should look like from a licensing point of view. What is your nirvana and what steps do you need to take to get there? Speak to as many stakeholders within the business as you can to understand the infrastructure, future and technical challenges that may be a speed bump on your road to optimisaiton.
If they have a SAM eco-system in place, but are not using it, then you can build upon what they already have. Think of this as a mini head-start. Sure, it might not be best practice or something you can re-enable straight away, but it is something you can turn into a positive. Get it back up and running, use guidance from things like ITIL, ISO standards and even the ITAM Review & SAM Charter for best practice processes. Consider it Day 0 of your new SAM function.
Finally, in order to get a better understanding of all of their IT Assets, go and speak to the AD team, SCCM team, IT Security team and any other inventory sources the organisation may have. You can then start to see how many unique assets are out there, what’s in one system but not another and start to see what you need to aim for.
I also like to engage with HR to get the latest numbers of employees (including contractors) so you can also look at quick wins within the SaaS licensing model by removing licenses from leavers and making sure only people who need licenses, have licenses.
Hope this helps, and more than open to explaining further as we started our journey in a similar stance in 2016, but without any form of SAM function and now have a verified (external party) Best Practice SAM function!