I am trying to implement the GTD system in my workflow, but there are some things I do not understand. For each project I work in, there is information spread across emails, mind maps, paper sheets and so on, so when it comes to define the next action, should I first have master plan prepared and then keep this list somewhere but just write down in the GTD system only the next action?
I use a GTD system that is tag-based. That way actions can be sorted by "when" but also by which "project" they relate to. For large projects, I create all the actions and use the action word at the end of the previous action to lead me to the next action (e.g. clean x to fix y). I keep the next actions as well as the reference materials both tagged by the project.
For sometime/maybe projects, I create the project and place a note in my reference material that lists all of the steps that I've thought through. That way when I decide to open up that project I can determine if any of the steps are fit for "now" or "next". When I do a review of my "sometimes" and "maybes" I will see the reference material note and determine if it gets moved up or stays where it is.
This is easy because I use evernote for my GTD system, but I think it would well for any electronic-tagging system. As far as maybe doing the 43 folder technique, I'm not too sure how it would be implemented - ticklers to review reference material?
If you have a long term plan (longer than just the next handful of actions), it would be useful to keep that as "reference material" that can be consulted at each weekly review and updated based on the outcomes of the week's new input and accomplished (or not accomplished) actions.
In my digital GTD system, I attach a note to each project to remind me where its reference material resides. Sometimes it's in a physical folder, sometimes it's in a Google doc, sometimes it's in email.
In summary, keep your master plan with your reference material, keep up to a week's worth of actions in the next action list. And don't skip the weekly review :)