The only item that should be in your context lists is item A. It is the Next Action. The others can be in project support.
Originally Posted by Globen
Or you can use a tool like Omnifocus that allows you to set projects to be sequential where actions you've planned ahead only show up once the action that is at the top of the list is completed. A lot of folks will point out that too much planning is usually not good as your actual true next action will change once you get there but I find in my world that many projects can be planned days or even years in advance and my next actions are still the correct once when I finally get there So I use Omnifocus, plan as many actions as I need to get the plan off my mind and set the project to sequential so I don't see anything that is not ready to be completed.
When I have multiple projects that have to be completed sequentially I set the last action in the parent project to be to go make active the child project(s). That way my active projects list isn't cluttered with project sitting with Waiting for's to be completed.
Oogie McGuire - Mac, iPhone & Omnifocus
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Paonia, CO USA