The best time is if you have the capital investment, you know the basic, the do's / don't and that's all about it. You're on your way of becoming well seasoned trader.
Anytime someone is become trader. I agrer that we need capital to trade because if you dont have money to trade its useless. The time is running you can start trading if you have capital for you to earn money.
No one could become a trader at any time that too particularly a good trader. Only after some mock trading experience and drills by developing some own strategies to test market fluctuations, a person could become a trader. Without them, trying to be a trader must be very dangerous as it will lead to big losses.