As I've mentioned before, I get an awful lot out of going to yoga, even once a week. If you've never tried it, I heartily recommend it.
Each class begins by setting an intention. We either find some quality we want to cultivate--patience or playfulness or ease or whatever--or we dedicate the practice to someone. Sometimes we do both.
Then my teacher ends this portion by reminding us that "While it takes strength to make a vow, it invariably gives strength." So, when the going gets rough and my quads are burning or my backbend is kinda puny, I am reminded to rededicate my efforts to the person I'm offering my practice to.
What's amazing is that even though they are not there in the class with me, when I remember that I'm doing something for someone else, I do better, I try harder, I care more.
Once I recognized this, I decided to apply it in other areas of life. I try to remember that it is as important to serve others as it is to serve oneself. Indeed, it may be more important.
This isn't to say you should cast off everything and go work in a soup-kitchen for the rest of your life. Instead, I encourage you to repeat these words when your friend is down and you really need to be a good listener. Or when your spouse is sick and relying on you for simple tasks. (Hi honey!) When I find myself getting distracted or frustrated or self-absorbed, I say to myself: "Be of service."
This can often be all I need to perform a task with a more giving heart and a better attitude. It can also often help me feel empathy and see things from another point of view, which is crucial to self-development and growth.
Look for moments that are difficult where you can say to yourself "be of service" and see what changes for you.