That varies a lot depending on what costume you're talking about.
ODST strapping is completely visible.
Spartans depend on which armor you're talking about. For my MK-VI there's very little that has to be strapped.
- Thighs have elastic belt loops to keep pulling up.
- Put on the back with two velcro that come over for the chest to connect to.
- Shoulders have a velcro that come down from the back, over the delts.
That's it for me. But the next person, in a different suit, different files, or a foam suit, is going to be different. So it would help if you specified what you're building beyond just "cosplay armor".
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