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Think about how much time you've wasted through the years by dwelling on things you can't change from the past, or worrying about things you can't predict or alter in the future. It can cause you a lot of stress and anxiety when you get lost in that way of thinking, especially when you recognize how powerless you are to alter the past or future. The only thing you can change is this present moment right now, and it starts with being mindful of where you are, what you're doing, and what is happening around you.  Observe what is happening around you without judgment. Simply notice your environment and any events unfolding around you. Try to describe (in your head, or out loud) your surroundings or any events happening in your immediate environment. Focus on concrete, observable sensory information.  Notice how you fit in with your environment. As you breathe in the air around you, walk across the ground, or sit quietly, recognize without judgment that you are temporarily a part of this place. There are many things that might distract you from enjoying a moment. In addition to the countless thoughts running through your head, you might easily become distracted by your electronic device(s). Incoming text messages, phone calls, emails, and social media updates can all distract you from whatever you're trying to do. Whether you want to spend quality time with others, or simply sit alone in a calm environment, your cellphone (or your friends' phones) can quickly ruin the moment.  Personal devices like cellphones and tablets can distract you from a moment, whether it's a moment spent alone or with others. Try scheduling your device usage, making time for device-free activities, or simply turning your phone off when you're trying to enjoy a moment alone or with others. You take countless breaths every day without even thinking about it, but actively concentrating on your breathing can help you live more consciously and mindfully. Focusing on your breath has been shown to help calm an anxious mind and return your attention to the present moment, which is a vital part of living mindfully.  Concentrate on the sensation of air flowing in through your nostrils and back out. Notice the way your breath feels on your nostrils, in your chest, and all the way down to your diaphragm (below your ribcage). Feel your belly rise and fall with each slow, deep breath. Any time your attention starts to drift to other thoughts, simply return your focus to the sensation and experience of breathing mindfully. It's easy to feel as though your thoughts are in control, especially during a crisis or moments of anxiety. But it's important to remember during these moments that you have the power to decide whether or not to engage with a given thought. With practice and mindfulness, you can eventually observe your thoughts and choose whether to dwell in those thoughts or let them pass you by.  An important component of mindfulness is accepting your thoughts as they are, without judging them, holding onto them, or resisting them. Remember that your thoughts are immaterial. They only gain meaning when you give them meaning. Do not try to push unpleasant thoughts away, as this may only make your mind dwell on the discomfort of that thought. Similarly, do not try to grasp at pleasant thoughts. Imagine each thought that drifts into your mind like clouds floating across the sky. If you do not like a particular thought, simply wait without engaging it and it will slowly pass by and drift away. It can be very easy to get lost in memories. There's nothing wrong with enjoying your past success or learning from your past mistakes - in fact, you actually should do those things. But dwelling on things that are no longer around or relevant, or obsessing about things you can't do anything about (like wishing you'd said/done something differently) will only cause you stress and anxiety.  It's important to recognize that there is nothing you can do in the present moment that can alter the past. Once you accept that you cannot change the past, you begin to take away its power over you. Think to yourself, "I cannot change the past, so what good will it do to worry about it?" Even though you cannot do anything to alter the past, you do have the option of controlling the present. By living mindfully, you determine how to live in this very moment. . You might be thinking about the future in anticipation (like waiting for the weekend) or in dread (like contemplating how bad Monday will be when your weekend is over). It's good to be motivated by your ambitions for the future, but dwelling on the future in any way makes you lose track of the present. It can make fun times go by more quickly, or it can fill you with a sense of dread as you anticipate things that you can't control in this moment.  When you think about the future, you forfeit your ability to fully be present in this very moment. Avoid looking at your watch, checking your cellphone, or anticipating anything that isn't relevant to what you're doing right now. Instead of getting caught up in what might/will happen, practice mindfulness and work to be present in this very moment. In this very moment you can decide how to act, what to say, which thoughts to engage with, and what mindset you will hold on to. These choices will affect your future, so it's important to make the most of what you can do in the here and now. You may be tempted to force some type of evaluation on the present moment. Perhaps you're thinking about how much better this moment is than a moment last week, or you might be thinking this moment would be made better if some other factor were different. However, these types of evaluations can hamper your ability to mindfully enjoy the present moment as it is. Instead, work to accept every moment, and let thoughts or emotions exist without imposing values or judgments.  Resist the urge to judge. Any kind of value statement/thought can be a judgment, even considering something "cool" or "fun" or "beautiful". Judgments extend beyond people and places. You may be judging the situation you're in, the weather you're exposed to, or even the thoughts running through your head. Mindfulness requires you to work at accepting things as they are without imposing value or judgment on them. This takes work, but once you are able to accept things in the present moment you will feel much more at peace. Any time you find yourself judging someone or something, try to catch yourself and stop yourself in mid-thought. Think to yourself, "I will let this pass without judgment," and try to let go of that thought. Try to recognize that enjoying this moment as it is, without judgment or desire, will make it that much more meaningful to you. That meaning will stay with you as a strong, positive memory of the present moment.

Summary:
Be present in the moment. Eliminate distractions. Focus on your breathing. Ignore fleeting thoughts. Let go of the past. Avoid thinking about the future Practice acceptance.