Routing allows questions to be shown or hidden based on answers to previous questions.

An example use case would be a  Net Promoter Score (NPS) question shows a feedback box question to understand why the person gave the score when the score given is less than 3.

If you wish to use routing - all the questions you require for the campaign must be added in the Campaign Designer. The order of how you want to show the questions must also be set in the Campaign Designer. When happy with the number of questions and the order you then use Routing to show or hide certain questions.

Configuring Routing Rules is done via the 'Routing' option in the campaign launcher. 

Simply drag the question from the right into the IF section.  If required combine questions with logic ( AND/OR ) and when happy add the 'THEN' question from the right-hand side. 

Toggling the SHOW/HIDE button to what you require to the 'THEN' question.  

You can give the Routing rule a name and have multiple Routing rules.