In my opinion i believe that signals are very much static in nature therefore it will fail in the dynamic nature of forex. Therefore it is better for everyone to understand the very nature of the market instead of signals. Check it out here how can you master the dynamic market using Bollinger Bands, Slow Stochastic, and MACD at
It is going to be very tough to master all the three indicators at once which may takes years. However you will learn the very foundation of the forex market it works just like the economic cycle where there is ups and downs of it.