1. Log into your MyGuestlist account
2. Click on the Guestlists tab (top menu)
3. Click on Upload Guestlists
You will then be displayed the following:
As per the instructions above, download the guestlist file by clicking on 'Guestlist.csv'
Once you have filled that in correctly, click on the Choose file button and navigate to the save point of your Guestlist.csv
Click the Upload button.