The first week
You open “Checklists and priorities” and do the first five items. They're almost always simple things nobody got round to: a homepage title that doesn't say what you do, page descriptions search has to invent because you don't have any, contact details that aren't on every page, images with no alt text.
Then you run the first article — on the topic with the highest search volume from your research. You read it, add your own experience and publish. You put five to ten keywords into rank tracking so you have a starting point.
A realistic expectation
Nothing shows in search yet, and that's normal. Google still has to visit your new page.