Why make a color swatch?
A color swatch is a separate sheet of paper with small samples of paint or other drawing materials. How necessary is it? I'll say right away - a swatch is essential for pan watercolors and markers. Often, pan watercolor paints look very similar, and until an artist memorizes the exact layout of the colors, it's easy to get confused. Therefore, it's better to have a sheet with samples and their positions at hand. As for markers, the colors on the caps often don't match the actual pigment. And in general, for convenience, it's better to select your intended palette of markers in advance, and to avoid wasting material, it's better to do this using a color chart. However, for opaque materials like gouache and acrylic, making a swatch is absolutely not necessary. Firstly, the artist most often doesn't use pure color but mixes them. And everything is clearly labeled on the tubes. Secondly, if you did pick the wrong shade, it's easy to fix with another layer of paint. Although, you can make a swatch out of curiosity as soon as you buy new material. I know everyone does it)) Do you use color swatches?
I've already gotten used to my watercolors, so I don't peek at my swatches anymore. But I can't imagine working with markers without one. Initially, I tried drawing without it, but there were a bunch of flaws and mistakes, and that's a medium that doesn't like mistakes. It's much more convenient with a swatch.