How to convert MTM tenants to annual leases?

[Peter Fokas]

The seller of the building I purchased a few months back had most of the tenants on a month to month agreement (no actual paper agreement). I want to convert them all to annual leases. What are the appropriate steps to take. This is in Newark, NJ. Can I just provide them new annual lease agreement and tell them they have 30 days to comply or move?
Do I need to give them any written notification prior to providing them new lease?