You've heard that tape has a million uses (specifically, the double-sided variety in this case)...
Forgo the expensive "fashion tape" (the only difference is marketing and pretty packaging) and cut custom sizes of good-ol' Scotch (or similar brand) to fit your need. Here are a few handy uses in the keeping-you-stylish realm:
• Secure the loose tail of a belt
• Temporarily fix a snagged hem (only works with lightweight fabrics)
• Seal down a plunging neckline
• Keep the back of your strapless bra from sliding up above the back of your dress or top/ Keep bra straps from falling down
• Close a gape in between buttons of a button-down shirt