For me its price action and trade management without a doubt. From experience, trying to use oscillators and moving averages...even the Traders Dynamic Index...just gives way too many false signals because there is so much noise in the markets. I don't use any indicators to tell me when to trade but I do use the 8 period RSI to give me some helpful insight. That is the only thing I ever have on my charts. Otherwise I draw trendlines and fib retracements. I trade on the philosophy that there is always a trend...you just have to find what time period its on. I follow the 15M, 30M, H1, H4, and D aggregations. I use the higher timeframes to develop my bias, and I trade off the lower time frames. There are a TON of places to find useful information on price action. The thread mentioned above on the PAST strategy is a good resource. Managing the trade is key. I can have 3 losing trades a day and only lose 15 pips or so and then hit one big one raking in 50-100 pips.
Knowing how to lose is just as important as knowing how to win...