Add the Security Template for the profile fields
From the Sitecore core database - create a Template called SalesforceAccountLookup under:
/sitecore/templates/System/Security/SalesforceAccountLookup
On the Builder tab of the new template, create Data section fields for each profile property that will be mapped. These will correspond with the values configured in Configuring the Profile Provider Account Lookup
Using the new template created above, create a record under:
/sitecore/system/Settings/Security/Profiles/SalesforceAccountLookup
Note the itemid GUID of this new item for the next step as it will be used for the defaultProfileItemID in the configuration of the domain.