Planning to remember: How to remember what you're doing and what you plan to do

Do you have problems remembering birthdays and anniversaries,
appointments and errands?

Do you sometimes find yourself in a room, and wonder why you're
there?

Do you end up doing things twice because you've forgotten you've
already done them?

Of all the memory failures that plague us, forgetting our intentions --
birthdays, appointments, errands we mean to do -- is the greatest, closely
followed by those moments of absentmindedness when we lose track of what we're
doing.

The special problem of ...