UI elements not showing up on World Space Canvas

I’ve created a World Space Canvas and want to start adding elements to it but none of them are showing up. I’m new to making UI’s and I feel like it is probably something really simple but I’m stuck. What I really want to do is to add an image component and stretch it to fill the whole canvas so that the world space canvas is completely white. (like at minute 4:10 in this video: Unity 4.6 - New UI World Space Canvas - YouTube) Any suggestions? Thank you in advance!

As an additional note, I am using the steamVR camera rig so not sure if that has an effect.