After creating record types and including picklist values in them, add record types to user profiles and assign a default record type for each profile. When you add a record type to a profile, users with that profile can assign that record type to records they create or edit.
Trial or Developer org Users:
Assigning Record Types to Profiles in the Original Profile User Interface
Customers:
Assigning Record Types to Profiles in the Original Profile User Interface
In the enhanced profile user interface, Record Types and Page Layout Assignments settings determine the record type and page layout assignment mappings that are used when users view records. They also determine which record types are available when users create or edit records.
Trial or Developer org Users:
Specifying Record Types and Page Layout Assignments in the Enhanced Profile User Interface
Customers:
Specifying Record Types and Page Layout Assignments in the Enhanced Profile User Interface