Your asking for tips suggests that you lack confidence in your ability to notice awakenings, which could be why you're not noticing awakenings. What you want to do requires motivation and it's easier to maintain motivation when you have confidence in your ability to do what you want to do.

Do something easier related to what you want to do. This way, you can achieve results to help you build confidence in your ability so that it's easier to do what you want to do. Rather than trying to notice awakenings, notice what happens in general while you're sleeping. It is easier to notice things in general than it is to only notice something specific. Notice more of what happens in general while you're sleeping and eventually you'll notice more dreams and the awakenings that come after those dreams.