Start with foundation garments, they're called that for a reason, then go shopping for a fancy dress or outfit.
The idea is to get a properly fitting bra, which is more of a challenge, or bustier then get a dress that goes over it. You will know once you have chosen a bra or bustier what fabric and style of dress will work. Bustiers have boning so light material or knits may not work. With a strapless bra there are many options in dress styles but each strapless fits differently in regards to the size range, depth of cups and plunge, or not, at the center front.
To get a custom one-piece look just add a shapewear garment to smooth and firm all the bits. The idea is to anchor it at the bra line with a snug, and properly, fitted bra.
Fantasie 4530 strapless
Va Bien Seamless Molded Solutions Molded Strapless Bra 509
A sleek seamless bra that is almost invisible under your clothes
The lightly contoured inner cups with plastic stay in center botton part in larger sizes
The gripper elastic on top back and all around bottom prevent the bra from slipping out of place and comes with removable clear straps which allow you to wear the bra with or without the straps
40-42B, 38-42C D, 32-40DD
The lightly contoured inner cups have a plastic stay in center bottom, in larger sizes. The gripper elastic on top back and all around bottom prevent the bra from slipping out of place. Comes with removable clear straps which allow you to wear the bra with or without the straps.
Chantelle 3065, with seamless contour cups
Smooth microfiber under-wire and demi cups provide comfortable support. Stay-put silicone along wings. Adjustable straps included which Converts to criss-cross, halter and traditional.
Body Wrap 44841 high-waist thong nude - Medium
Body Wrap 44821 high-waist long leg panty nude - Small to XL
The Body Wrap High Waist Long Leg is a seamless microfiber shaper that provides all-day firm body control in a high waist style. Flattens and slenderizes hips and thighs for a firmer looking you—instantly!
Body Wrap 45821 high-waist long leg panty nude - 1x 2x 3x
Body Wrap 44635 long tank black & nude - Large & XL
Smooth out from bust to hips with one easy step!
This Bodywrap long length shapewear camisole is constructed of stretch microfiber. Seamless, unlined soft cups feature a ruched center front for additional support and separation. Provides comfortable control that smooths and shapes from bust to hips. Fits up to a D cup with a No-rollhem.
Adjustable, close-set straps prevent slipping.