Understanding the impact of changes in multi-step flows

The startup where I currently work as a designer, offers a Saas platform geared towards School inspectors, and their substitute and contract teachers.

For one of their recent projects, I was tasked to design the interface for an intermediate step to serve platform's core machine learning  service. The step was to be placed inside the original flow, to allow school inspectors to cover the lectures using substitutes present to participate, thus called 'Preliminary Coverage'.

While the idea of designing one single step in itself does not sounds to be sophisticated, it introduces a number of challenges that, I will touch upon here.

First, similar to design of any part of a system, following usability heuristics saved me a lot of pain. In particular I can mention the three following heuristics: 

1. Visibility
The intermediary step should be designed in a way that provides clear distinction between elements of the different consecutive steps.

Dialog boxes state the purpose (or event), consequence of the event and available action.

2. Control
Being an in-between step , it was vital to offer users with enough control to choose the available actions, e.g. to go back, or to evoke en extra control during the flow. This also includes controls over elements that contribute to the visibility.

Adding enough control by covering the most natural user actions will allow them to feel in power in transitingin between steps.

Minimalism
It is tempting to add as as much information and UI elements to increase to control, and reach the desired visibility . But that would only cause clutter and more confusion. On top of that, clear microcopies, dialog messages and instruction is critical. 

Another important lesson learnt during this project was that adding even the simplest changes in the flow, and in particular in the middle of it, will most likely call for changes in the subsequent steps. This can include both minor tweaks and major changes to the design of  related steps.

Adding a new step to the flow imposed new changes to the following step, in that new visual cues were required to make the needed distinction.