How do I budget for Cyber Monday advertising?

As an e-commerce business owner, I'm struggling to allocate my marketing budget effectively for Cyber Monday. I want to maximize my return on ad spend without overspending or risking financial strain. My challenges include determining the right budget percentage, understanding competitive benchmarks, and creating a strategic allocation that balances potential revenue growth with realistic spending limits. I need a comprehensive approach to budgeting that considers my store's current performance, industry standards, and potential for scaling during this critical shopping period.