When I finally went onto anti-depressant medication in 2011, (which took three tries until my doctor and I could find the right medication for me), I wanted to be able to see at a glance whether the meds were working or not, and whether I was actually improving. And as depression is characterised by cycles of 'good' days and 'bad' days of varying length and intensity, when I cast my mind back over the weeks, I could not tell if I was improving or getting worse.
So as well as keeping a written diary of depression's details, I also began recording depression's 'good' days and 'bad' days on a one-year calendar. I recorded the 'bad' days (or parts thereof) in green and 'good' days in yellow. I also wrote down on which day I began each medication, and when the dosages were increased.
And the result was very encouraging. Even though I often feared (during the periods of emotionally/mentally painful and oppressively dark 'bad' days) that I was not improving - a simple glance at the calendar revealed that my fears were wrong - the proof was right there before my eyes - the number of yellow days were increasing. I was recovering from depression at last.
Below is the record I kept for 2011 and 2012. It was in mid-Feb 2011 that I mentally and emotionally collapsed, which was the lowest point of this bout of depression. At the moment I am experiencing about three weeks of 'good' days for each week of 'bad' days. And the 'bad' days are much weaker than they were previously.
Here is a link for a printable one-year calendar for 2013. Printable 2013 Calendar