Much of what I read in relation to addressing the challenges of dealing with modern life, in general, and to the specific needs of people with AD/HD and other executive functioning issues, offers mindfulness as a highly effective tool. 
Jon Kabat-Zinn defines mindfulness as, “…paying attention in a particular way; on purpose, in the present moment, and non-judgmentally.”
This takes practice!
As our ability to focus is eroded with various distractions, it is important to remember that, as Daniel Goleman says, “very strong research results (show) that a child’s ability to resist the temptation of distraction and stay focused predicts how she will fare financially and health-wise in adulthood.”  The italics are mine.
Following are two articles by Daniel Goleman.  The first addresses using mindfulness with children.  The second offers three particular ways for adults to remain focused.
Mindfulness is one of the most powerful tools we have.  It is free and easily accessible.  It is simple, yet not easy!