MACD is one of the most commonly known indicators. You can find a lot about it searching the web.
You can enable it on https://bitcoinwisdom.com/markets/bitstamp/btcusd under settings. The basic logic behind this is the following: MACD crosses up (turns from red to green) -> buy, MACD crosses down (turns from green to red) -> sell. This doesn't work very well on lower timeframes but can work on higher timeframes even though there are a lot of better indicators than that one. Anyway its still always useful to have an eye on it since quite a lot of people trade using it.