The phrase "extra splash" means adding more of something in a noticeable or exciting way. It implies going beyond what is necessary or typical to make something stand out or be more impressive. Full definition
I just got them a few days back, they're suitable for just about any type of outfit that needs a little extra splash of color. (poshscene.com)
To cut down on extra splash that can occur as your little boy learns to navigate his new bathroom habits, consider purchasing a seat designed with that exact purpose in mind. (wetheparents.org)
Instead, separate your feet from the ground with a pair of red flats and give your every look that extra splash of color. (thefashionablehousewife.com)