This is one big question which almost every amateur traders, who are very new to stock world, and cant hold nerves of the market.
I would say, entering in this field without knowledge or only a bit of knowledge is very very risky, it can wipe out your hard earned money in no time.
A trader becomes pro only when he/she knows all the techniques to stay in market, and they know which style suits them the most.
To be a trader, I would suggest to learn technical analysis and Options in depth.
Once done with the learning part, trade virtually and check on your accuracy.
A trader should be able to draw SL and TGT on charts with a good accuracy, this is key to discipline trading.
Once you take trade, keep a track of your accuracy and constantly work on it to improve your accuracy.
Trade with a strict target, once you achieve it, do not over trade just watch market.
Choose only those stocks which you find are good for you and giving you profit, no need to randomly choose stocks and bear unwanted losses.
A pro trader not the one who knows how to make money, but one who knows how to not loose money.
Hope it helps you.