Select the desired import from the dropdown menu. The query should read "Import is [Date of Import]" as shown below.
Click "Submit Query." This search shows the contacts uploaded from the import you chose.
Select the box next to the score column to select all contacts on the first page of results. To select all results from the search, click “select all in results” at the top of your screen.
A drop-down menu will appear, noting the number of contacts you have selected. Click the menu, and select "Add Tags."
Type all the tags you wish to add to these contacts. If the tag already exists in your Tag Library, it will appear here. If it does not, simply type the name of the new tag and press "Enter" and this will create the tag.