After reviewing the directions here, to create a scene using your own drawing squares or using a prepared sample set of squares, you would tap the button.
There is an "AutoCrop" feature which allows you to take a photo of a square, and as long as the entire square is within the photo this app will attempt to find its four corners and turn that photo of the square sheet into a square image, adjusting for camera perspective distortion.
There are times when the drawing itself contains rectangles which could confuse the automation, so you can also toggle AutoCrop to off (it defaults to "on") as needed. As you take each photo, it will import it based on the current state of the AutoCrop toggle switch.
If you have a previously-saved 360° image on your device which you would like to reload, you can tap the button instead.
(As a note, after photographing your six cube sides, when the preview appears, you can tap on that to save it for future use.)
If you choose to make a new 360° image, on the screen that appears you will neede tap each "direction square" one at a time to take photos of each corresponding square of your drawing.
As you do, observe the preview to check whether it appears to have been correctly taken (if not, tap the preview to retake that one).
If the "Please Try Again" image appears in the square, you might not have had the square sheet fully in the camera's view.
(It is, however, possible that your device does not have the memory and processing power that this app requires.)
If instead of your own drawings, you would like to use a sample set of drawings, then you can touch the button on that screen to load a sample image set.
When you have all six squares photographed and ready, you can choose to adjust the resolution for the combined image and then tap the button to join the images.
Once the combined image is ready, you can choose to save it for later use, and then tap the button to view.
(Note that after you choose to view it in VR, you can tap the
in the upper-right to come back to save it.)
If you want to redo any of the cube side captures, you can tap the button on the preview screen to return to the capture screen.
At that point, if your device has a gyroscope and compass, you can either move the device around as a "magic window" to see the immersive scene,
or tap the button to have the image split for use in a "cardboard" headset.
If your device lacks a gyroscope or compass, you can use your finger to drag the scene around to view the space.
Visit the Mobile Device CubeDraw Image Capture page to do this.