Once your nails are dry, you can proceed with creating the "water droplets." This technique uses clear nail polish to make the droplets, but you can also purchase gel.
While any clear polish will do, the best one to use is a quick-dry topcoat, which is glossy and will make your nails look wet and shiny. It also has the advantage of hardening quickly, which is ideal.
To give your nails a nice 3D texture, use the applicator brush to create the droplets by holding it at a 45-degree angle and tapping on it to drip small dots of polish onto your nails. You can make a cluster or spread them out, leaving plenty of space in between to create a water splatter effect. Just make sure the brush isn't too saturated, or else the polish might spread instead of making small dots.
Watch the YouTube video below for more guidance.