The word mindfulness is incorrect. What your experiencing actually is an 'empty mind' which allows you to be present in the moment. You can do this by using one thing as a focal point using any one of your senses i.e. truly tasting your food when you eat lunch, hearing the noises in your environment when you go for a walk, or feeling each and every key on your keyboard when you type. What this accomplishes at the end of the day is calming your nervous system. You will decompress and slow down. Thats when you find your zen space where you will experience restful alertness. You will naturally become more patient in that state. Get in the habit of doing this and it's rewarding.