Rose Marie,
I have used the "Sidetracked Home Executive" method of organization for
years.  It has helped in both organizing and remembering everything from
daily tasks of housework to keeping track of my pump rentals.  Basically
it is a card file system with a separate card for each task that is
filed according to the day it is to be done, then refiled for the next
time it is due.  When I remember to pull my cards and look at them, it
works very well especially for reminding me about those things that only
need doing rarely, but need doing regularly like changing furnace
filters, etc.  I also keep all my pump rentals on cards in the same file
so I know when each one is due back, etc.
Hope this helps.  I'm interested in other ideas as well.
Kris Rogers, IBCLC
Crystal Lake, Il