At the top right corner your business name appears. Clicking on it shows a dropdown menu listing all the business you can access. At the bottom of the list, click on + Add a New Business.

Set up the new business following the same process you used when setting up your first business.

Related article: Start Up Guide

Each business has its own separate TrulySmall Accounting subscription.
​Related article: Subscription and Billing

Remember to grant access to others who collaborate on the newly added business. Related article: Manage Users