Can I use my own picture as a web form background? Watch video
Yes. Any image URL can be used as a web form background.
To add a background image, choose Web forms and click to Create a form or Edit an existing form.
In the Design tab, use the Form Type dropdown menu and click Body, Header or Footer depending where you want to place an image. Click the show advanced link and enter the URL where the image is stored online. In the advanced settings section, you can also choose where to position the image and whether to repeat the image.