Besides that Fear & greed index indicator, I am more using the volume of chart or much better if the Relative Strength Indicator (RSI) also a momentum indicator.
Since using RSI on your chart, it also indicates if the momentum of the market, like if the chart is oversold or overbought. The higher timeframe you will use in your chart, it's much better in RSI, just my 2 cents.
RSI indicates only if the coin is oversold (below 40 lines) or overbought (abobe 40 lines). I use when I think the market will make some reversal. I applied this concept together with macd so that I can notice the momentum of the price. Fear and Greed are the most influential factors that affect the mindset of individual traders. We should fight our emotions so that we can trade based upon what we want to gain results.