Question to the designers of user interfaces.

Our company is young, we do not have a special designer for user interfaces yet ... Therefore, I decided to turn to the Habrasociety for advice / link / suggestion.

TASK
Solution:
Subtask 1 Solution (Step 1 -> Step 2 -> ... -> Step m1)
->
Sub-task 2 solution (step 1 -> step 2 -> ... -> Step m2 condition)
->
...
->
Sub-task n Decision ( Step 1 -> Step 2 -> ... -> Step mn)

So, to solve the problem the user needs to solve n subtasks. In order to solve the subtask, you need to go through a certain number of steps.
Passing a step involves entering some data by the user (for example, filling out a questionnaire).
During the passage of the step, the user sees all the previous solved subtasks and all the steps taken. He can return at any moment to any step in any subtask. In this case, the solved subtasks should somehow stand out and not take up too much space (well, you understand :).
In general, it all closely resembles the “master of something” from windows. But only reminds. How to visualize all this better ??? Maybe someone saw examples of something similar or have ideas on how best to do?

PS The interface will be developed on Windows Forms .NET. I promise to show the result and give the resulting code to everyone who responds :)

PPS
Example -
Task: registering a user in an organization.
Subtask 1: User information (Step 1 - Enter the name, year of birth, etc., Step 2 - Enter the data necessary for registration in the organization)
Subtask 2: Check the entered information.
(Step 1. Checking information by authority (it comes down to clicking the button is completed)
Step 2. Entering information in other departments.)
Subtask 3: Issuing a certificate of registration
(Step 1. Ordering the form.
Step 2. Printing on the form.
Step 3. Receiving customer certificate.)