This is an investor guide for investing in all stock portfolio (that means purely investing in stocks only, no bonds, mutual funds, ETF, etc.). Learners will learn all the minor and major details of investment in the stocks. An overview of the course is presented in the introduction section followed by the sections of how to open trading account, fund allocation, stock basics, stock selection and diversification, buy and sell stocks, common mistakes, and finally the summary. This course is designed carefully with the simplicity and easy to follow steps for beginner to advance level investors with emphasis on fundamental and technical knowledge of stocks, stock selection criteria and diversification method, when and how to buy and sell stocks, and how to avoid common mistakes as an investor. Supplemental material on how to do research and put buy/sell order is added in Section 4 and Section 6. One of the time consuming research for stock investor is to select the right stocks. In this course a list of stocks from various sectors is added as a supplementary material in Section 5. This list is comprehensive and a very good start to invest, however, students are free to explore other opportunities when skill is developed to research the stock properly. Making mistakes during investment is not uncommon, however, it is not acceptable to do theses mistakes with the hard earned money that we all worked hard to earn. Being knowledgeable and making decision comfortably can reduce the mistakes and help to preserve and grow the saving through this course.