2 step Approval Workflow

Hi,

I am New to Workflow Changes. Please suggest me the approach that should be taken for the below scenario.

I have a scenario where,

•   Workflow with 2 step approval required after Investigation is completed by Ivestigation Lead .
• 1st aprroval from Section Head
• 2nd approval from manager 

Validation : 1. If Manager Rejects it should go back to Section Head

                    2. If Section Head Rejects it should go Back to Investigation Lead.

Please provide your Inputs.

Thanks in Advance.