Drupal 7 - How to set editor´s role

First you have to create role called "editor" here admin/people

Than you have to visit permissions page admin/people/permissions

And add permissions to the editor :

• Use contextual links
• Access administration menu ( or Toolbar and Shortcuts)
• Use the Full HTML text format
• Access the content overview page
• Bypass content access control

These setting will allow to your clients easily change almost everything what usuall client need to make changes on web page withou allowing to change something crucial.