Change embed width or application width?

Change embed width or application width?

How can I change the size of the iframe when I embed the code on a site? I have tried adjusting the width value which will change the size of what you but the form itself ends up getting cut off. How can I make the form fit inside the frame width I need?

I'm not worried about height but on the width I need 468 pixels in width and I think the default is at 500px. Any help would be greatly appreciated!

If I can't change the embed width is there any way to change the application width itself?