Corporate Style Flow Diagram Design

I have an existing PowerPoint presentation that requires enhancement. Specifically, I need a graphic flow diagram created on a single page, with the diagram reflecting key processes. The remaining slides also need to be made more professional in a corporate style. The final flow diagram should be delivered in PowerPoint format.

Ideal skills and experience for the job include:
- Proficiency in PowerPoint
- Graphic design skills
- Experience with creating flow diagrams
- Ability to work in a corporate style