In trading activity alone does not make money, the right activity at the right time is what makes money. Many times the right thing, is to do nothing.
In your actual trading you have to do four things very well to make money.
You have to know when to get in.
Only enter trades that have the highest probability of success and the best risk/reward ratio. Buy the best monster stocks during up trends. Short the fallen leaders when the game changes and they are under the 50 day. Buy the monster stocks at the gift of the 200 day moving average. Short down trending junk stocks. Go where the trends are.
You have to know when to get out.
When your trade reverses through a key support get out. When the market trend changes get out of your long positions. When your stop loss is hit, get out. When the stock reverses and hits your trailing stop, get out.
You have to know when to stay in.
If you enter a stock with the potential to trend let it run as far as it will go. Do not set a target, just trail your winner with a stop. Let the stock tell you when it is done running. Do not cut your winners short.
And most importantly you have to know when to stay out.
If you do not know what to do, do nothing. If the charts confuse you, stay out. If the volatility is escalating and you are losing in every trade, stay out. If you are a trend trader and you see no potential trends, stay out. If you want to go long but all the stocks you want are going down, stay out.