Conversion from Salesforce to Zoho

Conversion from Salesforce to Zoho

I am interested in converting from salesforce to zoho and would like the conversion steps as well as instructions on best practices/methods to migrate users to the new system.  With salesforce we had unlimited training up until this past year when they cancelled Premier Training without informing us.  I want to ensure with the new system we can migrate as easitly as possible.  I am working on entering in all the custom fields and objects.  I have recently requested the export of all data from salesforce. With all the data transfer or should I export by object. Such as Accounts, Contacts, Opportunities, etc.  All the activity history is very important to us as well.
 
I look forward to your response.
 
Kimberly