Short term memory is a bit flaky. To start with my wife made me write down what I had to do at the start of each day, and then keep looking at the list through the day; go through the list at the end of the day and see how I did. Also, kept a small note book and a pencil with me (this is before IPhones) so I could write down anything I had to follow up.
Then I read that we memorise better in pictures rather than words (the really good Brain Injury Workbook shows how to do this) so now I associate things I have to remember (names, places, things I have to do) with the most crazy, colourful images I can think of. Works for me.