Mix & match different textures & lengths, it will give more personality to your outfits.
Wearing an all black outfit doesn't mean that you shouldn't have fun with your accessories! A simple black belt with gold detailing will look incredible with any outfit while a classic hat will finish off your whole look.
Also think about details on your clothes. A sequin blazer or a fringed top will give your whole outfit a new vibe.
If you're not feeling a full solid black outfit, aim for sheer fabrics. A sheer blouse will give a more delicate and feminine feel to your look.
Finally, think about volumes. A pair of skinny leather trousers will be a great contrast against an oversized chunky knit and will give more allure to your outfit.