i think we need to spend more the then 6 month on the demo account after that we can get lot of practice on the demo account and practice and now we can win very huge profit in the forex market we always need to stay in touch with the forex market, and open your trade after look at the trend of the market. most of the forex forums said you have to spend few months or some of them said three months but really it is not exactly true because the time you can spend using demo account depends on the person where there is differences between people and their views . I think the period of the time for any person to use demo account depends of his goal of using the demo account