I usually use the EU pair because of its high volatility. And several times when big news comes from other currencies like JPY or CHF I also redeem it. I use TF from M5 and M15 because when my position is open it gives me tension so most of my trade is closed in 1 to 2 hours. the couple must be minimum so we can master some pairs in a good way and then exchange them in a better way. the best strategy is we make the perfect plan for the first couple and when we are sure that we have mastered then move on to the other couple