A Workflow Rule sets workflow actions into motion when its designated conditions are met. You can configure workflow actions to execute immediately when a record meets the conditions in your workflow rule, or set time triggers that execute the workflow actions on a specific day. If a workflow action has not executed yet, you can view and modify it in the Workflow Queue.
Creating Workflow Rules

To manage workflow rules, click Your Name | Setup | App Setup | Create | Workflow & Approvals | Workflow Rules | New.
Select the Object

- Select Object (custom or standard) to which you want this workflow rule to apply.
- Click on Next button.
Configure Rule Settings & Criteria

- Enter a Rule Name.
- Optionally, enter a Description for the rule.
- Choose the Evaluation Criteria.
- Enter your Rule Criteria.
- Click Save & Next.
Configure Workflow Actions

- To add an immediate workflow action, click Add Workflow Action in the Immediate Workflow Actions.
- To add a time-dependent workflow action, click Add Time Trigger in the Time-Dependent Workflow Actions.
Configure additional immediate or time-dependent actions. - Click Done.
Activate the Workflow Rule

Click on Activate to start the workflow rule.