You can add new picklist options to a new field by navigating through setup and editing record types.

1. Navigate to Setup > Create > Objects.
2. Click the object name.
3. In the Record Types section, perform the following for each record type:
   1. Click the record type.
   2. Click Edit for the field.
   3. Add all Available Values to Selected Values list.
   4. In the Default field, click and select the option values.
   5. Click Save.