There is no golden rule to it, the best strategy is based upon hit and trial, to be honest, 80% of traders use all the indicators on default settings and have been doing pretty well using these settings only, but tweaking indicators might help you in getting some early triggers but obviously as the number of triggers would increase the profitability from each trigger would definitely go low, traders make this compromise and adjust their Risk/ Reward accordingly to make sure that they are in a correct trade, also no one would give their holy grail if they have one because if you share a trading strategy with someone, it really stops working. this is a great rumour in the trading community and everyone really obeys the rumour.