How do I manage discount budgets across seasonal fluctuations?

As an e-commerce business owner, I'm struggling with maintaining consistent profitability during seasonal sales periods. My current discount strategy lacks a systematic approach to managing budgets during high-traffic events like Black Friday, holiday seasons, and end-of-season clearances. I need a comprehensive method to allocate resources, predict potential revenue impacts, and ensure that my promotional spending doesn't erode my profit margins. How can I create a robust framework for managing discount budgets that adapts to seasonal variations while maintaining financial health?