The employee Responsible for the opportunity can see two parallel scales at the top of the opportunity form illustrating the state flow: Customer centric stage and Sales stage.
Customer centric stage shows the state, at which the potential customer company is at the moment. The Sales stage shows the stage your company is currently at. These stages move concurrently. The employee Responsible for the opportunity can move the sales stages by clicking the next stage. If some fields need to be filled in order to move to the next stage, they are hifghlighted with red.
The passed stages are colored with blue, the current stage is green and the future stages are grey.
Further you can find the description of the stages included in the "out-of-the-box" CRM application. You can edit these stages and add the new ones in section Opportunity Stages.
Opportunity state flow
Customer centric stage
Sales stage
Description of the sales stage
The field of the Documents tab that needs to be filled to move to the next sales stage