Alerts can be displayed two ways. Each alert has an audio alert, chart marker and can be shown as a market on the chart and in the respective alert window for the platform.
NinjaTrader - NinjaTrader Control Centre -> File -> New -> Alerts
OEC Trader/S5 Trader - Charts & Quote -> Custom Indicators -> Log
MultiCharts.NET - File -> New –> Order & Position Tracker window -> Alerts tab
It is essential to understand that these alerts do not represent buy and sell signals. We do default to blue and red for the alert colors but this does not mean that blue = buy and red = sell. For example, we have an iceberg alert. If the iceberg is on the offer side, you will see a red triangle. Still, if you watch the icebergs on the offer, you will notice that most often this does NOT hold the market. That is not to say you can fade all icebergs. Alerts must be taken in context. Where do they appear in the grand scheme of things? Are we seeing a group of alerts of the same type at this point? Are we seeing icebergs and divergences and large quantity traded alerts all at the same time?
For icebergs, the remaining quantity is worth noting. If you see 750 contracts traded against a 500 contract bid and there are 500 contracts left, it is more significant that if there are only 50 contracts left. Effectively at this stage, the iceberg is usually done when there are so few contracts remaining.