Trading is:
80% Psychology
10% Risk Control
10% Execution
Your might have a good trading system,yet not be a profitable trader,to be a successful trader goes beyond drawing lines on your screen or a few indicators.
Work on yourself consistently and intentionally first and the rest comes easy!
Knowing indicators is just part of what to know about trading, it can not help you to make profit all the time. Sometimes, your indicators will tell you where the market is going, but the market will go the opposite direction. You are correct about this.
But trading is more about strategies and risk management which will take up 60 to 70% of it. Mathematics is also part of it. Although viewing the chart, using TP and SL on the exchange you are using can be enough. But there are some calculations you will want to make before trading.