Steps
1. First, download the DCF file from Nexpart. http://nexpart.com/admin
2. Save the file to your desktop
3. Open the file with Excel and save-as a comma delimited file with the file extension .txt
4. Navigate your browser to http://www.yourb2csite.com/dcfupload.wws
5. Browse to the file and process it
You are done.
Do a test of your site by searching for a part by number and by application. Make sure the brand names look good. If they do not, you goofed it up and need to start over.