Step

Install GESync managed package from Salesforce AppExchange:
https://appexchange.salesforce.com/listingDetail?listingId=a0N3000000B5KuWEAV
Note: use default options during install.

Step

Download and install GESync On-Premises or sign up for GESync Cloud.

Step

On-Premises only. Request trial license.

Step

Configure a synchronization profile and start synchronization. Read more in the documentation.