...
Install the Send2CRM Essentials Salesforce package:https://login.salesforce.com/packaging/installPackage.apexp?p0=04tDo000000xmTGIAY
Send2CRM Essentials on AppExchange
We recommend installing the package for admin users only. The necessary permissions can be easily applied using the included permission set.
...
After installation of the Essentials package above, optionally install the Send2CRM Analytics package:
https://login.salesforce.com/packaging/installPackage.apexp?p0=04tDo000000xmsGIAQSend2CRM Professional on AppExchange
Again this should be installed for admin users only. The included permission sets should be assigned after installation.
...