This is completely up to you, clicking publish in the website editor pushes your website live onto the web for all to see. However, don't forget, just because your website is live it doesn't mean visitors will be flocking to it immediately.
The best way forward is to get the bulk of your content on your website, check it and publish. This will get your website out there and get you listed on search engines, spend some time optimizing your website afterwards and publishing as and when you need to.