My short-term memory is somewhat poor, too. If it comforts anyone, my long-term memory isn't good either (not really an Aspie-trait).
One suggestion. When I was tested for it I used two methods to get better results: 1. Clustering (grouping one digit numbers into 3 digit clusters); 2. Using these clusters and auditory memory simultaneously, i.e. part of the information stored in normal numeric short-time memory and part of it sored in short-term auditory memory, unprocessed. Despite doing this I performed average at best, I think.
Now I'm more accepting relying on to-do lists (checklists) whenever I feel the need. Besides, by repeating 2-3 items in my head a few of times in the morning I usually I remember what particular things I have to arrange during the day, well, after some hard thinking...
Playing memory board game with a 5.5 yo child and his mother ranked me steadily at 3rd place, after his mother. ![Razz :P](./images/smilies/icon_razz.gif)
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Another non-English speaking - DX'd at age 38
"Aut viam inveniam aut faciam." (Hannibal) - Latin for "I'll either find a way or make one."