What do you mean by launch day? Is this simply going live quietly or going live with a big bang?
I've never taken the big bang approach.
Went live with www.skilledup.life (free talent for tech startups) on 1st Aug 2020.
I think it's important to have a plan in place, with the main tasks you'd like to get done on that day, and that will help you achieve the goals you've set for your launch. However, it's also important to leave some time for fun, as it's a crazy 24-hour marathon.