First off all VWAP stands for Volume Weighted Average Price which just means its showing the average market movement based on volume. Institutions use this to identify premium and discount zones.
So above in the image you can see a median line that price is trading around this is like the point of control in amt logic so from this understanding the median line is just where price has traded the most on average and its illustrated by a line going through the middle of price
The lines below and above are standard deviation bands which can show if price will reverse and basically again in amt logic extremes of the premium and discount. The band above is a negative and positive 2 and 2.5 you can use 3 if you want but it rarely touches it.
Usually the deviations +1 and -1 act as a type of premium and discount in the market and remember the +2 and -2 are the tops of the extremes of premium and discount
The higher we go in premium the higher the chance that we reverse soon because that is an ideal situation for institutions to get in. Be aware of trading falling knifes tho, if there is no confirmation or the draws are very clearly higher, dont trade against it.
Trades above the 1 and ideally the 2 is what you should be taking because when we are that much deviated the probabilities are very high that an institution which is trying to get filled is going to get filled at the best price.