This book is so helpful at laying out the 8 stages of Shamatha meditation, and telling you the mental signs that you have progressed to each stage
Learning Dzogchen will also help, but many teachers will tell you if you havent got a strong Shamatha practice, its very difficult to get the full utility of Dzogchen.
Have you checked out this free course with Allan?:
About 20+ videos of great meditations and teaching on dream practices.