Create a paths-layer and then enable edit-paths mode.
EDIT: The UI is pretty much staying as-is, it's been under development for 3 years and while there are some things I wish I had in mind earlier during development the plan now is to finish the major features and get to beta sooner rather than later so we're going to go with a built-in help/tutorial/walkthrough mode that hilights what users must do in order to achieve different things. Have you looked at the included User Guide? It documents everything the UI exposes to users and explains a lot. It's updated for each released version.