Ruth,
I use a watch with multi-alarms in it. They are hard to find, but good old TIMEX makes one called the "EXPEDITION" it has lots of other stuff on it that I don't use, but it only costs about $30- $40. It has 3 or 4 alarms on it, I only use 3 of the alarms so I am not even sure if it has 4 (it is not the prettiest watch, it looks like a sport watch, but when it comes to LOWS, who cares what it looks like).
I set my alarms to go off at 10 am, morning snack (first low of the day), 3 pm, afternoon snack (second low of the day) and 6 pm to make sure I eat dinner on time.
It works for me as I have not had a dangerous low ever since I got the watch. My wife loves it as she has not had to call 911 ever since I got the watch (about 6 years), believe me all the Firemen know my address by heart.
Bob