Read Chapters 8th, 9 and 10 of the Law of construction

8th Chapter Requirements Analysis
Software requirement analysis is the software feasibility analysis of software planning during the elaboration and refinement, analysis of various possible solutions, and assigned to the various software elements. Demand analysis is the final step in the software definition phase, which is to determine what the system must accomplish, which is to put forward complete, accurate, clear and specific requirements for the target system.
NABCD model is a good application of the present development project.
One way. Making every step of the budget is a good way to improve your efficiency.
9th. Project Manager:

Software project Manager refers to both extensive computer expertise and project management skills, the ability to accurately analyze and manage the cost, personnel, schedule, quality, risk, and safety of software projects so that software projects can be successfully completed according to scheduled plans.

10th. Typical users and scenarios

This comic is a good illustration of our user scenario. Haha, you know what you're feeling.

Read Chapters 8th, 9 and 10 of the Law of construction