Click the gear icon in Gmail and select “See all settings” from the Quick Settings menu.

Navigate to "Filters and Blocked Addresses" in the top menu.

Select "Create a new filter."

Add "mg.goodshuffle.com" and "goodshuffle.com" in the "From" field.

Click "Create filter."

Check "Never send it to Spam" in the checkbox

Clicking the "Create filter" button brings up a new window. Here’s where you actually specify that I’m whitelisting an email. In Gmail, you do this by checking the “Never send it to spam: box."

Doing so will ensure that emails that meet the criteria you specified (in this case, emails from the Goodshuffle Pro) never end up in Spam or Trash (unless you move them there manually).

Click "Create filter."

Once this information is specified, you can click the create filter button, which creates the whitelist within Gmail.