Sometimes you need to edit a field that’s not approved yet.
Click a custom object and the field you want to edit.
In the Fields tab, click Field Actions and Edit Field.
Make your changes and click Save.
You can’t edit the API Name.
The changes appear in the Fields listing.
When you don’t need a field in a custom object anymore, you can delete it.
In the Fields tab, click Field Actions and Delete Field.
Make sure you really want to delete the field before you pull the trigger! Click Delete.