When you save an image from Vellum, it saves into a new album called Vellum. This makes it simple to find the wallpapers.
Open the Settings.app
Select "Choose a New Wallpaper"
Scroll and select the Vellum Album
Choose the Wallpaper you'd like to use
Zoom/Move the wallpaper to where you'd like.
Choose either "Still" or "Perspective"
Select which screen you'd like the image for.
We suggest using blurred images for the Home Screen and More contrasted images for the Lock Screen.
That's all there is to it!