Be mindful of what you have. Really notice and be thankful for everything that makes your life the rich, comfortable, abundant gift it is. 
this can be a complete mood turner if your head is off somewhere - anxious about what may or may not happen in the future or regretting the past, worrying about all you have to do and what you didn't do, stressing about how other people should be .........
Just stop and notice what you are missing while your head is off somewhere, and be grateful.