Break your music up into small sections. First, try to master a 2 or a 4 measure section.
First, try to Count the section of the music. Count it a few times – until you get good at it!
Then, try to Sing the section of the music – Sing it a few times – until you are able to sing it at the same speed that you counted it
Then, play the section of music several times – until you are able to play it at the same speed that you counted it and sang it!
Then, move on to a new section – the next 2 or 4 measures. Do the same routine.
After you master a few sections of music, try to combine the sections. Before you know it, you will have mastered the entire song!
Use the ‘Checklist’ for your song. If you are perfect at the first few sections, don’t play those sections again. It is better to use your time to work on the other sections that you are having difficulty with.