Step 1: Go to the and pick the previous month's fully formed candle. If the previous month's candle does not have a large body relative to the rest of the order flow, then it is perfectly acceptable to go back two months and pick that candle instead.
Step 2: If it is a candle draw your Fibonacci levels from the high of the candle to its low. If it is a candle draw your Fibonacci levels from the low of the candle to its high.
Step 3: Switch to a lower timeframe ( and lower) and observe how price reacts to the Fibonacci levels as support / resistance
Step 4: The following month re-draw your Fibonacci levels if required
1)On my charts I include the 1.272 and 1.414 levels as well as the 2.0 level. These are not automatically visible
2)You can also 'reverse' the levels (simply draw them in the opposite direction or use the reverse function in the Fibonacci tool's settings) if the current month's price action violates the 0 level. This does not happen often.
Example: AUDUSD . I have drawn the Fibonacci levels from the low to the high of the October Monthly Candle
Now look at the same Fibonacci levels on the Hourly Timeframe. I have highlighted clear rejections in November of Fibonacci levels that can be used as entry points and the elongated shows a clear demand region near the 1.00 level.