Tudumo's number 1 design goal is to help you focus on your work. That means keep important information visible, and hide distractions.
Everything is aimed at adding your actions quickly, keeping upfront 'organization' to a minimum and using filters to arrange your view according to your current needs. Some concepts, to get you started:
The simplest way to use Tudumo is to create simple actions. Each action is just the next possible thing to do that will take your closer to a given goal.
If you have many tasks and need some structure, e.g. for a project (e.g. "Deliver report") or life area (e.g. "Exercise"), create headings for them. You can then filter out all other actions and headings by clicking on the "focus" icon (>) on the right-hand side of the heading.
You become a Tudumo black-belt by using tags. Tags are small (usually one word) text snippets separated by commas that you can use to represent one or more actions - e.g. "@Home, weekend". They seem trivial but allow you great freedom to create ad-hoc groupings, and filter by them.
If you're a bit unsure of whether to use tags or headings, just start playing around and you'll quickly find what suits you. It's a really good idea to learn a few of the more important shortcut keys. Start with three or four of them - I promise that you'll enjoy Tudumo more if you do!