Get Everything Done

I do not (yet) manage anyone, so you might need to take my thoughts with a grain of salt. But...

My very first thought was to use something like 3T. Give your subordinate several tasks: a queue. As they finish stuff, assign more so that there's always something in their queue. Since they will always have something they can be working on, it gives you the freedom to refill their queue at your leisure... or when your intuition tells you that you should.

My second thought: Assign and delegate anything and everything that's appropriate as soon as its appropriate. Trust that your subordinate is capable of managing and working their own task list. A good manager hires people he can trust and trust them he does. If you have to micro-manage someone by working with them one task at a time, maybe it's not their work you should be looking at but their time-management skills instead.

There are times when I work with others and rely on them accomplishing things. For these, I use a follow-up method that I learned here (possibly from you... or Seraphim?... or Matt?...). I have a task of "Follow up with <xxx> about <yyy>". I add the date and the number of times I've followed up before with them to the beginning of this task.
"(1 - 4/27) Follow up with Alan about delegation"
The date guides my intuition on when I should follow up again. The # of follow-ups guides my intuition on stepping up the priority / visibility.