I keep a shopping list text file on my computer desk-top, and it is set up with each category in the same order of the departments that I come to when I begin shopping in the supermarket, (i.e. dairy, processed meats, chips and drinks, produce, etc.)
I simply use self-discipline in maintaining the list and then printing it out before shopping. It has really helped keep my budget and impulse buying under control.
Being on my computer desk-top has made it easy to maintain. Adding is easy, and when I return from shopping I simply erase those entries I purchased, and leave those I didn't.
"Food is our common ground, a universal experience." - James Beard