Neville Goddard took a very simple approach to letting go.
Neville didn't need to obsess over the things he wanted to manifest. He didn't constantly visualize or think about what he wanted to create.
For Neville, letting go was as easy as “assuming the state of the wish fulfilled.”
You become for a moment, after a successful meditation, incapable of continuing the act, as though it were a physical creative act. You are just as impotent after you have prayed successfully as you are after the physical creative act. When satisfaction is yours, you no longer hunger for it. If the hunger persists you did not explode the idea within you, you did not actually succeed in becoming conscious of being that which you wanted to be. There was still that thirst when you came out of the deep….
When you pray believe that you have received, and you shall receive. When the physical creative act is completed, the sinew which is upon the hollow of man's thigh shrinks, and man finds himself impotent or halted. In like matter when a man prays successfully he believes that he is already that which he desired to be, therefore he cannot continue desiring to be that which he is already conscious of being. At the moment of satisfaction, physical and psychological, something goes out which in time bears witness to man's creative power.”
Neville knew that if he visualized his scene correctly to manifest his desire, he would automatically let go of his desire. He would have a feeling of satisfaction – a feeling that he had already achieved his desire.
He didn't need to look for signs that his desire was manifesting. He had already experienced the feeling that it was real, and that was enough.
Neville didn't visualize to try to change his physical reality. He visualized to create the feeling of having manifested his goal.
As Neville went about his day, he understood that his job was to train his mind to focus on living from the state of his wish being fulfilled. His job wasn't to think about his desire or about his current life. His job was to live from the feeling of already having manifested his desire.
When he achieved and lived from that feeling, Neville was detached from the outcome. He knew that the world would transform around him to match his state of being, or imagination as Neville called it.
When you're thinking about your desires or your current life, you create anxiety, doubt, and obsession. You focus on wanting something to happen and wonder how it's going to happen. These both imply that it hasn't happened. They also cause you to try to control the outcome and make things happen (the how) – which is the Universe's job, not yours.
The true vine (and what creates your circumstance) is your own wonderful human imagination. When you believe this you will no longer imagine as you formerly did, but will prune your thoughts every minute of every day. You will break the habit of feeling remorseful, depressed or regretful. You will no longer think unkindly about another, because you will know that he is actually yourself pushed out, and appeared in your world because the Father in you called him.” – Neville Goddard
Pruning your thoughts (or vines) occurs when you notice that you are thinking about something. You may be worried that something won't happen or fearing that the worst will happen. You may even be running past conversations through your head wishing you could have said or done something differently.
When this happens, you want to prune your thoughts and intentionally shift your attention so that you feel, see, and think from the point of your desire having already manifested.
It's no longer something you're hoping will happen or wanting to happen. It isn't something that is happening. It has happened. It is real NOW!
When you imagine, God is acting. He is the true vine and the vinedresser, for he is your imagination, imagining you. If you really understand this, you will start pruning your thoughts. If you don't…, you will persist in allowing your wanton energy to run wild, to swell into irregular twigs, and bear unlovely things in your world.” – Neville Goddard
Neville understood that letting go occurs when you are at one with your desire – when you live as if it is already yours.
Letting go is true detachment. There's no worry, fear, or obsession. You trust that it's yours because you know that it is. The evidence is already within you and in your life.
It doesn't matter what the world says.
All you have to do is let go by assuming the state of your wish fulfilled.