I use Waterfall for most of my small projects (i.e. Wordpress Websites). These projects go through the following stages:
For larger projects, I break down the project into sprints.
My strategy when it comes to developing SaaS or Apps is to get to a Minimum Viable Product
I create client portals in Notion where I keep information about Projects, Sprints, and Deliverables
I use Loom to record short videos. I instruct my clients to provide feedback using short videos.
My clients are not techically savvy, so I tend to have Video Conference calls or meetings to discuss projects and gather information.
Before any meeting, I emails participants a short list of things we will dicuss. I also prepare a slideshow presentation to help us stay focused during the meetings
Desirability: My clients usually want what their competitors have plus some things that diferrentiate them. I help them align this with what their ideal customers need.
Feasibility: I help them determine if we have the skills and resources to do it
Viability: I help them determine if we have the skills and resources to maintain it
I learned this the hard way after launching a few apps to crickets. What really makes the client happy is not just features, it is features that solve problems for users. It is the act of building a business around features that solve problems for users.
These are some of the way I help my clients generate demand for their applications: