How do you create banded columns in Cognos Report Studio?
Here is an example of banded columns taken from this link:

EDIT:
Maybe this search string will help find this page?
"Cognos Report Studio, how to create column band"
Here is the procedure for a list:
- Select the list object
- In the Structure menu, select Headers & Footers and then List Headers & Footers
- Check the box next to List Page Header and click OK
- In the List object properties set the Column Titles property to At start of details
- Select the new header
- In the Structure menu, select Headers & Footers and then Insert List Row Cells Above...
- Enter the number of header rows you want above the standard detail header and click OK
- Delete the List Page Header row with 1 cell that was created in step 3
- Select multiple horizontally-adjacent cells that you want to merge into one
- In the Structure menu, select Headers & Footers and then Merge List Row Cells
Add some styling to the new header rows and end up with something like this:

Note that I couldn't vertically merge cells to produce the tall 'Sales Person' header in your mock-up. There may be a way to do this but that goes beyond the scope of this question.