How can I get my embedded form in Wix to open in a new window?

I followed these instructions to the letter, and my form is there, but I need for it to open in a new window. How do I do that?

I would suggest you to select the "Code" option in the "HTML Settings" while adding the form to your Wix site, then copy the code to add the form in a pop up window, the code can be found under the publish tab, embed section and clicking on the "Pop-Up" option:

Copy the given code: 

Hope this helps.