I prefer to use dual EMA crossover however it is best to identify overall trend and not necessarily as entry signal per se.
Note that 50-day and 200-day is heavily watched on Wall Street, so one thing I like to do is scan for stocks bearishly breaking the 50-day, and if the sector they belong is also weak, AND the market trend is down, I will think about shorting them.
I use 50/100 EMA to determine bull/bear/lethargic-sideways condition, using the SP 500, NASDAQ as index
Once I get a feel for overall market, I will check which individual stocks I may want to trade.
These stocks must be in strong performing sectors (long) or weak sectors (short)
So......--->
1) Market Trend
2) Sector Trend
3) Individual stock trend
you want all 3 to be in sync
once that is done, I look at volume, price action, etc to pick my stocks
note I may only see 2 or 3 "great" stocks a month which meet the above criteria. This is not day trading