Firstly we need a datum to measure from, well the earth revolves 360 in 24Hrs = 15 degrees per hour or 0.25 degrees per minute. So I tried midnight initially and I was always out by one hour. Common sense said try 23:00Hrs. This worked.
I chose the one hour chart as it worked well with the method as 60min = 15 degrees so 45degrees is three bars giving the Gann angle of 45 degrees. This makes tracking time intraday easy.
Firstly notice what happens every three bars. This alone serves notice of an impending change.
This is as simple as it gets. Try it or just observe until confidence grows.