Once you have followed the download links you will be required to log into your Salesforce Organisation where you will be presented a screen similar to the one below.
Follow the Salesforce installer steps to complete package installation.
Grant access to all users .
and check the acknowledgment of installing a Non-Salesforce App and then click the Install button:
Install complete.
Next Step
Customize Contact and/or Lead Page Layout (Version 3.0) (Pre-Sitecore 9)
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