When should I start building my email list for Black Friday?

As an e-commerce business owner preparing for the critical Black Friday and holiday shopping season, I'm trying to understand the optimal timeline for email list building. I know email marketing can be incredibly powerful during holiday sales, but I'm unsure about when to start collecting emails, how to create momentum, and what strategies will help me maximize my list's potential before the big shopping weekend. I want to ensure I'm not too early or too late in my list-building efforts and that I'm creating genuine engagement rather than just collecting email addresses.