Here are some recommendations to help you with that:
1. The simpler the cut of your dress is, the more elegant or fancy and embellished the evening bag can be, and vice versa - the more elaborate the dress is, the plainer the evening bag should be.
2. An envelope clutch, a flapover clutch or minaudiere go better with a fitted or semi-fitted outfit, and a pouch is best with full skirts and full skirt dresses made of soft fabrics that drape.
3. A patent leather clutch will look great with a cocktail or long evening gown at a gala event.
4. Silver or gold evening bags always go with an evening outfit of any color.
5. One more tip: wear the right nail polish.
For example, if an evening bag is a solid neutral or dark color, then the nail polish can be bright or dark: burgundy, chocolate, fuchsia, coral, red, etc.
If an evening bag is bright and/or lavishly decorated, then your nail polish should be neutral.
And of course, always remember that looking your best and being the best-dressed lady in the room is possible only when all colors, color combinations, lines, sizes, shapes, etc. are in accordance with your Beauty Code.