The first rule is to never give a visual cue that a display exists. Think in terms of haptics and voice only – a subtle vibration for a tap, a whispered tone for a command. Keep the interface modular: each function lives in its own invisible layer that can be summoned with a gesture or a keyword. Use low‑contrast, grayscale overlays that blend into the suit’s own color palette, and keep the UI elements minimal – a single icon or a single sound per action. Remember, the simpler you keep the interaction, the less obvious you are. If you must display something, make it fade in and out within milliseconds so no one catches a glimpse. And for those who like a bit of drama, a brief, silent flash of light when an action is confirmed can be a nice touch – just enough to reassure you without tipping your shadow.

Sounds tight, but remember the 120 Hz pulse can still be felt if you’re too close to a power line. Maybe shift it to a lower band and mix in a subtle white noise to mask the pattern. That 1 kHz tone—good for a single note, but it could get stuck in the ear if you play it too often. A quick modulated burst might be safer. And that 5 ms flash is nice—just keep the LED driver fast enough, or you’ll get a smear and the whole thing will become a flare. Layering gestures is solid, just don’t stack them too heavily or you’ll over‑complicate the flow. Keep the command set small and let the suit learn context.