Day to night outfits aren't unreachable and they can be achieved instantly. As we all know 'day' outfits tend to be softer when it comes to accessories and makeup and those are exactly what needs to change to perfect the look.
In addition never be afraid to experiment as most fashion garments have the ability to be dressed up or down. For example a spaghetti strap dress can be dressed down with a white tee.
Also, flat shoes don't necessarily need to be swapped with heeled ones but that of course that completely depends on the occasion and the look you are aiming for.
Lastly, longer earrings and a dark lipstick are your best allies and what would I recommend is for everyone to keep them close.