If bra rides up at back: Try adjusting the hook and eye closure to tighten, and loosen bra straps. Otherwise, try a smaller band size (for instance a size 34 instead of 36).
If band digs in under bust: Order one band size larger (for example size 36 instead of 34). Another option is to opt for a bra with a wider band.
If there’s bulges on the sides: Order one band size larger (for example a size 36 rather than 34), or a larger cup size so the breast is completely encased within. Another option is to go for a style that offers a better coverage on the side-wings.
If cups overflow: Order one cup size larger (for instance from C to D); or one band size larger (34 to 36). Or opt for a fuller coverage bra instead of a half-cup bra.
If shoulder straps dig in: Loosen bra straps or alternatively, opt for a bra with wider straps. Also try on a smaller band size because the under-band of bra could be too loose thus leaving the shoulder straps to do all the support.
If bustline sags: Shorten bra straps and avoid stretchy fabrics; alternatively, choose a firmer support style with rigid straps.
If underwires pinch or poke: Order one cup size larger (say from cup B to C) or try a non-underwire soft cup style.
If straps slip from shoulders: Tighten straps or opt for bra with wider straps.
If Center Front of bra doesn’t lie flat against the body but lifts away instead: Opt for a bra with a larger cup size.