Plan your collage and then gather the resources you need to create your vision. Save the images and vector art effects in an album on your iPad camera roll for easy access.
Choose an image to use as your background.
Start to extract the other images from their backgrounds.
Select the "cut out" tool and start with the "smart brush". Make sure you have the setting on "subtract" and then start to paint away the background. To refine your selection you can "feather" the edges. You can also refine your selection by using the basic brush, zooming in on your image by swiping out with your fingers. This allows you to carefully select the fine detail.
Start to position your images on the canvas.
Create a new layer and remove the background from your next image. You can also set the "edges" and apply smoothing if you wish.
Create vector png files in Adobe Illustrator and add those in another layer.
You can resize any layer by selecting it and then scaling and moving your object with two fingers.
Play around with the opacity of each layer (you can access this menu by double tapping on a layer).
Have a play with the "looks" in the looks menu. Looks can be selectively applied with the smart brush.
Time to refine your ideas. Declutter by removing unnecessary elements.
When happy, export!
Save to your camera roll, share on social media or refine it further in Photoshop CC.