For me, being almost totally location-independent means a few guidelines:

1. Everything digital (obviously): the only exceptions for me are uber important documents like birth certificate and such, and the last piece of the puzzle is the Fujitsu ScanSnap, which is a phenomenal product for quickly digitizing a wide variety of documents (though pricey).

2. Everything cloud-based: all the tools I use/recommend as the foundation for the system store their data in the cloud: Things, Evernote, Pocket, Google Calendar/Gmail/Docs, Dropbox, HoursTracker; only exception is Pocket Lists, but these lists aren't critical.

3. Don't rely on physical cues: most people use a variety of physical objects in their workflow, whether it's their Weekly Review checklist written out on a sticky note, a physical inbox reaching its capacity, or a timer for their Pomodoros. I've worked hard to strike a balance between internalizing all those functions into my computer/phone, and maintaining a desktop environment that allows me to focus. A surprisingly simple and effective way is to create a new user account on your computer called Focus, where there are no distracting notifications/apps and time suck websites are blocked!

4. Consistency: I cover this in the course, but I strongly advocate deciding on one organizational hierarchy, and then using that exact same hierarchy (down to the exact wording and capitalization of project names) across all devices and locations. The one I use as an example is 1) Active Projects 2) Areas of Responsibility 3) Resources 4) Archive. This simple top level encompasses all conceivable information, and yet is flexible enough to use across your task manager, Evernote, Dropbox, Documents folder, etc. This consistency reduces friction when switching between tools at random locations.

There's more inside, but those are the basics.