If you want  steps to be hidden by default, and only show when a condition is met, select ‘Hide by default’ under step builder Basics:

hide-by-default

This will make sure users going through the steps in the process only see the steps relevant, rather than all the steps.

Hidden steps appear with a green eye with a cross on it:

screenshot-2016-10-19-14-35-38

 

After you have done this, you can build out your conditions to show the steps.