If you want to view supporting business information, click the Show Worksheet icon on the project for which you wish to enter a forecast.
Click Edit.
If necessary, use the drop-down list to change which forecast rows can be edited:
To enter a total project forecast, which includes forecasts for contributing sub-projects, select Enter Project Total to make the Total Forecast rows editable (assuming that you have permission to edit them).
To enter a forecast for an individual project (that is, excluding forecasts made by sub-projects) select Enter Project Contribution to make the This Project rows editable (assuming that you have permission to edit them). If configured by your administrator, the forecast categories may be populated with suggested values based on project actuals and backlog records.
Enter values for each forecast category: you can press TAB to move the entry field to the right and SHIFT+TAB to move it to the left.
Click Save.
Depending on whether you entered a total or contributing project forecast, the relevant forecast row will automatically calculate revised figures. For example, let's say that the total Commit forecasted amount is 10,000 USD, with sub-project forecasts contributing 1,000 USD. If you enter 12,000 USD for the Commit value on the This Forecast row, the total forecast amount will increase to 13,000 USD after you click Save.
To create a project forecast from the object detail view:
Ensure that the Include In Forecasting checkbox is selected on the project for which you want to create a new forecast.
Click New Forecast in the Forecasts related list of the project detail page.