In this video (by cywei99), the author explains how the Subliminal Power software works.
You will discover how you can customize your own messages according to your needs.
Remember to ALWAYS use positive affirmation.
Regarding my experience, I do sometimes add music that helps me to concentrate such as alpha waves.
Also, even though it might seem surprising for some people, I have changed the size and color font of the flashing messages.
I know that the idea behind the subliminal message is not to be noticed, however, I had the impression that the results were quite slow.
The messages are still running very fast on the screen, most of the time I can barely read them!
Believe me or not, I have noticed a significant improvement since these modifications. So, you should check it out for you as well if you have the feeling that things are not moving as you wish.
Finally, you have to test different option and see what work best for you.