In Word 2003:
Open the Tools Menu >> Letters and Mailings >> Mail Merge.
Select Labels and click Next
Click on Label Options and select your tent card and click OK and then Next
Select Use Existing List and click Browse to find your Excel document. Click Next.
Add in the fields you want on your cards to the first and then click Update All Labels.
Finish Mail Merge Wizard.
-- Word 2003 doesn't come with the 5302 label template. You'll need to download that from http://support.microsoft.com
In Word 2007
Select Mailings from the menu list at the top,
Click on Start Mail Merge and select Labels
Select Label vendor Avery US Letter
Select your product number 5302 and click OK
Click on Select Recipients from the top and select Use Existing List to browse to your Excel document
Using the buttons on the top for Address Block/Greeting/etc add in the fields you want to the first label.
Click on Update Labels
Click on Finish and Merge