System architecture charts can be incredibly complex, and I need to include them sales/investor presentation for almost every client that I work with. They serve an important purpose: 1) demonstrate that you know what you are doing on an emotional level, 2) ability to answer detailed technology questions on a factual level.
As I dig into these puzzles, I discover that in most cases the diagram is very complex, but the underlying system architecture is not. Most diagrams are created with some kind of drawing tool. Their main purpose is system specification, make sure that people are designing the right system. They are not meant at all for communication. (In that respect things are similar to Excel: a great tool for analysis, a poor tool for communication).
The solution is to disconnect from the diagramming app and start sketching your system architecture again, purely for the purpose of communication.
- Grid, grid, grid. Line up all the boxes properly, space things out. Keep boxes the same size/shape as much as possible
- Eliminate as many overlapping connectors as you can. Try again, again, again, again, and one more time. Overlap spaghetti is a sign that you have not really understood how to explain your architecture.
- After you eliminated your overlaps, you should be left with a grouping of boxes that is more or less logical. If there is a sequential process, there is a high chance that your boxes line up according to it. If things are related, they are probably located next to each other. In the previous steps, you looked purely for overlapping connectors, now go over your diagram again and think about function.
- Next, use color to group things together. The great thing about color is that it can make a connection between objects which are not necessarily sitting next to each other on the page
- Omit, collapse boxes that are not that important (this would have disastrous consequences if we did this in the system design diagram)
- Think hard about what text, titles to use in the boxes, cut words where you can, use rectangular instead of circular shapes to fit more text if needed. Go for a smaller font size, but don't fill the entire box with text to make your composition look calmer.