i generally like to see signs of longer term accumulation, like months of range-trading near the lows. accumulating in the range after a downtrend is usually the highest-gaining strategy, but if it breaks below the range you need to stomach pretty heavy drawdowns. alternatively, you look for signs that the range is broken to the upside. use price pivots and horizontal resistance for this, as well as other tools like %BB.
remember, "overbought" and "up 50%" don't mean that much in altcoin markets, when the trend is up. we are talking about exponential gains. it's tempting to ignore a coin because its price has already doubled, but sometimes that coin will end up gaining 10x or 100x.
Thanks really insightful...
the only way avoid this is to get educated and doing more research i think...