The business plan is a scientific methodological tool that allows an entrepreneur or entrepreneur to assess the feasibility, resources, viability and sustainability of their business idea. This article aims to translate the whole theory of how to develop and advance a plan for business, to provide guidance to entrepreneurs. Start with the market research which should identify the product, its features, price, acceptance of it and calculate the demand for it is continuous with the technical study which analyzes the value chain, the distribution in the plant , equipment, machinery and suitability for their production or service delivery, continued its administrative study identifying the structure, roles and profiles, together with the calculation of labor and finally performs the economic and financial evaluation to determine whether is profitable and sustainable over time. The methodology used was the theoretical review of literature on entrepreneurship, business ideas, business plans and project evaluation.