Yes, we can. for now, i trade using indicator, but sometimes i dont use any indicator also. There are many trading system which dont use any indicator and we can use it to make profit without any indicator it is possible. It is possible to trade in forex with just the help of trends. But using indicators will help more to make profits. It will help us to determine the perfect time to enter the market so that more profits can be earned. There are a group of traders doing that and they are called naked traders. They rely on charts, trend lines and fibonacci for making their analysis.