Customize

The header picture has to be  a horizontal picture.  You have to have a photo that is short and long to fit 

Choose a photo that is wide enough horizontally to fit within the parameters of the rectangle they give you.

To make uploading a photo as a header easier, make sure that it fits the dimensions of a Google Form. Otherwise, you will have to cut off a lot of it. It needs to be in a 4:1 aspect ratio.

I found it easiest to search for banners as it will give you the dimensions you need to fit in the header space.  I saved it to my drive and uploaded it.  Easy peasy.

The dimensions of the header for forms is 1600 x 400 pixels.  I used google drawing and set the page up to have these dimensions and then created a custom header using my own graphic and text.  I still didn't get it perfect as the question section sort of blocks some of the header.  Definitely need to play around with the sizing and location to get it just right.  I would suggest that once you get one that works well save it as a template and then go back to adjust and customize it to be more appropriate for each form.  

- Check file size and dimensions
- Name your file something you can easily find
- Save the file in a location where you can easily find it

When searching online for images to use as headers for Forms, it is best to save them to your hard drive (or Google Drive if using a Chromebook) in a common Pictures folder. If you save several images in this folder at a time, you can create an image bank to choose from in the future to save time. This way, you will be able to locate the images easily.