There is no one 'best' plan as each person has different risk tolerance, time frame and objectives. Do your research before you start investing. Research can include talking to relevant professionals and asking questions on here (although this is an academic website).
One of the world's greatest investors in terms of long-term track record is Warren Buffett who provides a great deal of free reading material on the Berkshire Hathaway website, which you can easily find on Google. I explain the fundamentals in chapters 2 and 3 of the attached too, if it helps.
Thesis An analytical tool to aid the reflective selection of equity...