When you set your intention, you focus the energy everywhere around and within you to the creation of the ideas of your mind.  You focus the very substance of God in your life.  Think about it this way: When you wake up in the morning, do you decide what you want the day to be like, or do you just let the day unfold and then decide if it was a good day or a bad day?  Do you react to what happens, rather than using your power of intention to shape the happenings of the day?  Let's look at how the power of intention can manifest abundance in our lives.
Try this experiment this week: Every morning, wake up and decide that you are going to be present.  Every morning, state, "I intend to be present for the people and events in my life."  Then, imagine yourself doing something that you have planned for you - going to the gym, to work, or lunch with an old friend.  All through the day, remind yourself of your intention by affirming, "I am present."  No matter what happens in your day, keep reminding yourself, "I am present."
By setting your mind to presence, you are literally programming the operating system in your mind to observe the reality around you.  This simple act wakes you up, and, once you are awake, you are able to choose rather than to allow, to respond rather than to react.  You move from someone to whom life just happens or someone on the sidelines, to someone who is fully in the flow of life.
Don't believe me?  Try it!  Really try it for a week, and see what happens in your life.