First, be sure your data in the spreadsheet is arranged in columns.


Then, in step 3 Customize 

• On the left click on Import Data and select Start Import/Merge 

 

• Next, select Browse for File and locate your spreadsheet (Available file types: .xls, xlsx and csv).  If you get an error, try saving your file as a .csv and re-upload.

• In Choose Fields, confirm your list and uncheck the first row if you have headers.  You can also use the up/down arrows in the top row of grey checkboxes to sort the columns alphabetically or numerically.  If everything looks correct, move forward to the next step.
• Arrange your fields by dragging and dropping Available Fields to Arrange Fields 
• Double click or drag and drop the field from the left to set up information how you would like it to appear (see example below - info on different lines)

• Click Next
• Click on Finish - Once you click finish you have completed the merge process.

 

Video Demo