Listen to your words and listen even more closely to your thoughts. Why? Because your words and your thoughts will determine your actions. One of the things that has helped me to listen to my thoughts has been to keep a journal. It is not necessary for you to write in it everyday, but it helps to record various insights you gain as you go about living your life. Instead of using a big notebook, you might use a small note pad that you can keep in your purse or pocket for easy access to record your thoughts as they occur to you. (I've found that if I don't immediately write down ideas and insights as they come, it's hard to remember them later, at least with the same degree of clarity.) Whichever method you choose, what's most important is that you write your thoughts down. It will help you know what's in your heart.
Be honest with yourself by paying attention to your actions. Actions speak louder than words, and they always tell the truth. What do your actions say about you? If you say you love your job, but your actions say otherwise, which do you think is more true - your words or your actions? On the other hand, if you say you're not good at a certain job, but your actions say otherwise, that's also important. What do you do with this insight? You can use it to make more beneficial choices in your life. By being honest with yourself based on your previous actions, your actions moving forward will be based on truth instead of just what you tell yourself.
Take time out during the day for quiet time to listen to your inner voice. I call this inner voice the voice of God. This is similar to point number one, but it takes it a step further - beyond the natural mind to the supernatural heart. You may want to use your quiet time to meditate or pray. However you use this time, the key is to shut out all of the noise around you by focusing deep within yourself. Breathing deeply during quiet time will also help you focus. I know it's hard to find quiet time during a particularly busy day, but it's so important - even if it's just 10 minutes a day and you have to sneak away to get it. Quiet time can really make a difference in your life. It enables you to hear God speaking to your heart reminding you of His perfect love for you.