Back in the last century I worked for an engineering company. That experience taught me the value of thinking with my hand. Engineers loved working with white boards and diagram apps to map out processes and procedures in a work flow.
If you’re new to diagramming, Shapes is a good app to start visual thinking. Drop in shapes, link them together with lines, add text. That’s just about all there is to it.
The left Sidebar contains all the shapes you’ll need to create a diagram, a flow chart, or an organizational chart. Just drag and drop.
Each shape can be edited, too. Change the colors, fill type, add shadow, change the stroke size and color, and more.
Shapes can be grouped together with a click. Add any font you need and change size, color, and shadow. Shapes isn’t quite as extensive as Diagrammix but it’s also 1/4th the price.