The installation procedure includes the following steps:
Run the ArcGIS for Desktop setup program
Download the setup files and run setup.exe. For more information on installing ArcGIS for Desktop, see Installing ArcGIS for Desktop on your computer.
Complete the steps in the ArcGIS Administrator Wizard
After installation is complete, the ArcGIS Administrator Wizard is launched. Select your product type. If you will be using a concurrent-use product, you will need to define your 10.3.1 license manager. If you will be using a single-use product, you will need to authorize your software for use. If you are upgrading from a previous release, your authorization information will be retained for 10.3.1 use.
For more information on the License Manager, see The License Manager.
For more information on authorizing your software for use, see Authorizing your software.
Your ArcGIS software is now available for use.