. I’ve been using this for years and admit the interface isn’t at the funky end of the scale (in fact, the last update was 2014. But then the colour wheel was invented by Isaac Newton in 1666). Still, Paletton is a powerful palette builder, with tons of preview and export options. Drag around the outer dial to select an initial palette, sliding the inner-wheel dots to adjust shades.
Also try … Adobe Color
. While Color is open to all, you have to log in to your Adobe account to save or export palettes. Check out the ‘accessibility tools’ that give a pass or fail rating for different colour combinations.
I often like to project a strong single colour, with a relief colour that doesn’t steal the spotlight. Selecting monochromatic (variations of the same base colour) or analogous (adjacent colours on the wheel) is a good start, while choosing complementary colours (opposite sides of the wheel), or triadic (thirds) delivers more dramatic contrasts.