When we want to achieve a healthier lifestyle, this usually means establishing new habits, which is not an instantaneous thing to do. Habits become habitual through purposeful repetition. The best way to establish a new activity as a habit is to consciously schedule it into your daily routine.
Need to exercise more regularly? Schedule two days a week to meet your buddy at the gym and put it in your weekly calendar app. Should you be stretching a few minutes every hour you are at your computer? Set an online alarm. Have you been putting off sending thank you notes? Commit to writing one every day before breakfast.
Want to walk for 15 minutes after lunch? Put that in your daily planner. Trying to add meditation to your stress reduction strategies? Tell your family that the first 15 minutes after you arrive home from work are your time to shut the door to your room and sit quietly. Do dirty dishes tend to piled up in the sink? Remind yourself to wash them after each meal before returning to other activities.
Having a set schedule for the new activity gives you a sense of control over that aspect of your new, improved lifestyle.