This is a great question and the simple answer is: the more you visualize, the faster it will manifest.
When you spend 5 minutes seeing something in a day, that has a bit of an impact. You see it for a few minutes and it has a bit of a chance of getting into your subconscious.
When you spend 20 minutes seeing something in a day, you have a much greater chance of letting it seep into your subconscious and you spent more time focusing on it.
The amount of time you spend seeing it matters and how focused you are when you are seeing it matters too.
If you are waiting for certain news, see the document in your inbox (for example) and spend a good amount of time seeing each letter and each word written there. Imagine whom the email with the good news will be from and how they will have worded the letter.
What you put into it you will get out of it. I’ll say that again because it is very important: what you put into it you will get out of it.
What works for me is to get to a quiet space, close my eyes and focus the eyes of my heart, asking the Holy Spirit help me to see it in lots of detail and by injecting lots of happy emotion and gratitude into all that I am seeing.
Now, what if you have only 5 minutes in your day to spend on this? What if the rest of the time, you are busy with the many things you have to do and you simply don’t have more than that time to see it? Then take those 5 minutes and make sure (as much as you can) that you are focusing on it.
Praying for More Time
If you find that you do not have as much time as you would like to visualize, pray for more time. Ask the Holy Spirit to open up time in your day to see this and to give you a superior concentration. God has an awesome way of opening time up in your day. A friend of mine prayed for that and all of a sudden, her husband announced that he would be able to work from work for part of the week, freeing her up from her mommy duties and she was able to increase her visualizing time 5-fold.
Always ask God for help, to arrange things for you and to make things possible for you in a way that you may not be seeing. He has ways that you and I do not.