You need to add values to the Record Type in Salesforce.
Salesforce Record types let you offer different business processes, picklist values, and page layouts to different users.
Salesforce's default configuration is that when fields are added there are no values selected, hence the field appears grayed out in the page layout until it is configured.
To select picklist field values for a record type:
- Go to Setup > Customize > [Record Name, eg. Opportunities] > Record Types
- Click Edit next to a picklist field and select the values you wish to make available