The benefit of a Membership Site is that you can launch it with Bare Minimum Content and continue to Add More as you go!
You can preload about 6-8 weeks of content and use content dripping to make the content available based on a set schedule. And while your students consume that content, you can continue to add more content and add it to your drip sequence.
Ofcourse you need to have a content plan and you need to be very clear about what your members get initially, what they are going to get every week or every month because if you don't keep your members engaged and interested in your upcoming content, they are not going to stick around.
Create a content calendar so you know exactly what's due when as this way you won't miss content delivery dates. Make sure your content is ready and added to the drip sequence before the due date.
Email members every week so they know what's available that week and what's coming next. But the great thing about membership site is, you can create your content whenever you want! Just upload it before the due date and your audience will not know if you created it yesterday or was it all pre-loaded when they purchased your membership program!
As long as whatever content you make available to your members initially is complete in itself, and fits well with your overall plan and ultimate goal for your membership program, that's all you need to get it off the ground.