Is it follow up with a disgruntled customer? Is it send a hand written thank you note to a happy customer? Is it a follow up email? A phone call?
If you wait until you have the time to do IT, it may be too late. And as someone said, the best way to eat an elephant is one bite at a time.
A friend of mine keeps a small notebook with him everywhere he goes and writes down stuff he needs to remember, or do. He has 10 years of these spiral bound notebooks. A former CEO of mine does the same thing, except hers is leather bound.
Commit to doing this once a day, and watch your life transform.