Research Methods in Psychology
            
        
            
    
    
                
            Jhangiani, R. S., Chiang, I. A., Cuttler, C., & Leighton, D. C. (2019). Research methods in psychology.  The Saylor Foundation. https://kpu.pressbooks.pub/psychmethods4e/chapter/developing-a-hypothesis/ 
Read Chapters 9 & 10. These chapters explain how to create a good research question, how to use a hypothesis to test theories, and how to create a good hypothesis for a research study.