After some fiddling around, I think I got it working. What I did was:
- opened up the Settings application
- picked the site in the top left select
- opened up the Content tab
- selected the page I want to use as the default page, under Web site Content
Now if I open up the Pages application, I see a master page with 3 'subpages' I created: homepage, subpage and subpage 2. When I browse to the evironment, I see the elements from the master page (header, footer) and in between I see the content from the homepage. Clicking on the subpage or subpage 2 menu items, the content changes accordingly.
Not the full 100% sure this is the correct road to take, but it works as I want it to work. So I'm a happy developer (=