Navigate to Salesforce's Appexchange
1. Install the Axsy Retail Execution App on AppExchange. You will need to assign your users a license for the Axsy ReX Mobile App Managed Package.
2. Optionally, install Axsy Smart Forms on AppExchange. This package is free so licences will be assigned to all users. Please see here for more information: Smart Forms Portal
For more on how to navigate AppExchange, please see this Trailhead by Salesforce: Install AppExchange Packages