To do this task
Have a paper copy of your forecast at your side while you make changes and print a report that lets you see forecast amounts.
Open the QuickBooks Business Planner.
Click Set Up Forecast.
Select the forecast and, if necessary, the customer or job and class that describe your forecast.
When QuickBooks displays the monthly forecast amounts, change the amounts as desired.
Repeat steps 3 through 6 for each forecast as needed.