Scroll down to the Add Attachments section.
Tap the section and the following will expand, tap + Add Attachments.
Choose from the following options for your attachments:
Choose from files. Opens your general file folder from your device.
Choose from images. Opens your photo folder from your device.
Open Camera. Uses your camera so that you can take a photo to upload.
Select the file(s) that you want to upload.
Tap Finish to attach the file(s)!
Note: There is a 2GB limit for individual attachments.