When you attend a yoga class, often you are asked to set yourself an intention. Sometimes this can be as simple as dedicating your practice to someone that needs your energy - someone you love, or even someone that you are not getting along with. Other times you can dedicate your practice to yourself, with an intention.
To be honest, most of the time when I hit the mat I bring the intention of samtosa, one of the niyamas, observances, from Patanjali's Yoga Sutras. Samtosa can be translated as contentment.
Contentment, something quite intangible to many these days. As we're pushed to achieve, to strive, to be better, sometimes we forget what we have, where we are, who we are and what is truly important to us. For me samtosa, contentment, has had the most positive effect on me and my yoga practice.
If you boil down to why I practice yoga, and perhaps why I usually dedicate my practice to myself, it's because I take the time to be thankful for and remember what I already have. To be kinder, more loving, more generous and understanding with those around me. To put it bluntly, I try to be a nicer person for those who share my life.
If I could teach only one thing in yoga, it is for us all to be a little kinder to ourselves. Combining ahimsa, non-violence (to ourselves) with samtosa, contentment really cuts to the heart of yoga. Don't hurt your body or your mind, be mindful of what you already have, and be happy to be exactly where you are. Start each day, each task, each pose exactly where you are now, not trying to be something you're not and not wishing for something else. Be a little kinder to yourself.