Fields from your event are displayed in the middle Available Fields area. Click the field(s) to move them to the Selected Fields area and add them to your report.
You can also select fields from other forms by selecting the form in the Forms area on the far left and drilling down into the form to select the field you want to add to your report.
Click Save to save your fields and move to the area where you can download your report.
Click beside a field to remove the column from the report.