No matter what cup size you have, keeping your strapless bra from dropping down your torso is an issue. Even with tiny movement, your strapless bra can move, leaving you uncomfortable and your girls a bit exposed.
To avoid this potential embarassing moment, try this clever trick: Use the strap that comes with your strapless bra, snap it on the hook of your bra, and wrap it around your torso as a belt! This way, your boobs and bra are secured, and you won't need to worry about giving a peep show!
Here's a video from The Rachael Ray Show you can refer to as visual reference: