What is the most logical next event?

How to use a manual typewriter
Slide the margin set on the right-hand side of the typewriter.
Before you start typing, you'll want to make sure that your margins are set correctly. The right-hand margin set is usually located next to the larger carriage release lever at the top right of the typewriter.
The margin sets usually look like metal brackets at the very top of the typewriter. They may have a button you have to press before you can move them.