Using Color Trends as a Guide
For 2019 the color trends are minimalistic, bold, vivid, light/dark color schemes, duotones, complex gradients. These articles by Venngage and Behance, on Graphic Design trends, with discussion on color use, further expand these ideas. For color guides, there is no better resource than Pantone.
Avoid personal color biases, which can cloud the decision process. Your audience may not have the same reactions to a particular color that you have. Try to be objective. What may be a negative to you may be a positive to your customer. No color is bad, just maybe not right for your brand.
Using Color Theory as a Guide
Color Harmony. Choosing between analogous, (colors next to each other on the color wheel: yellow/yellow green/green, orange/red orange/red, etc.) or complementary, (colors opposite each other on the color wheel: red/green, blue/orange, purple/yellow), is a matter of what works the best for your design and transmits the feeling of your brand.
Color Context. Colors appear different next to other colors, the same purple against a white background will look different against a blue background.
Warm vs Cool. Red, orange, yellow are considered warm. Grey, blue, black are cool. Hues can also determine temperature, warm grey, a cool yellow are some examples.
Achromatic. Unsaturated color, neutral. Examples of an achromatic are browns, tan, black, grey, pastels, white.
Tints, Tones and Shades. Pink, taupe, powder blue are some examples. Adding white makes a color a tint, adding grey, a tone, and adding black makes it a shade. Further explanation can be found in this article.
More detail on color theory can be found in this Wiki article.
Hopefully this has been helpful in understanding the importance of a well-considered color palate for your brand style.
Below is a fun infographic about color created by 99designs.com