A good mix of pictures to keep on your phone that can pop up randomly is a great idea!
My suggestion is to make sure you've covered each one of your likes and dislikes in your pictures! There can be one picture to count for two or more. But all of them should be accounted for.
I've also done on/off for lock and homscreen. Same pose on the picture but clothed on lock screen and naked on home screen. An idea if you want to pair them!
My suggestion for humiliating picture:
Naked holes filled and upside down, where your but is above your head tongue out, optional body writing too
All holes filled and visible staring in the camera
Close up of pussy and ass. normal, filled, and stretched
Close up of you licking your toys or with a toy down your throat
Just some to get you started.
Also as an option you can makes live wallpaper that can do videos!
