To dream of seeing a woman wearing a garter belt represents a desirable situation that is ensuring itself. Something you want in life guaranteeing itself or making you aware of it being guaranteed. Confidently anticipating a desired outcome. You may be very confident in knowing you can have or do something.
To dream of wearing a garter belt represents your own attempts to ensure a situation, or “bend over backwards” making sure something will happen. Alternatively, wearing a garter belt could also reflect your eagerness to proposition someone else.