Disarming lever - small square flat plate that you have to put your fingers behind (hold your hand out, palm up - you get the idea) to swing up to the disarm position. This requires little effort. When armed, the flat, flush plate completes the word "ARMED".
Door lever - a round "barrel" handle which you GRIP, much larger than arming lever. It swings in a much bigger arc than the arming lever and requires a lot more effort.
So one has ARMED and needs fingers to operate, the other is orange and has to be GRIPPED and heaved up to open the door. I'm not sure what else could be done to make them any more different.
If the door is opened from the outside then the slide should disarm.