Simply select any shape, text, solid, or other color property, and click a color from the palette to apply.
<aside> 🔥 Right Click changes stroke!
To save you the hassle of having to open properties in the timeline just to find the stroke property, I have dedicated right-clicking a swatch to strokes.
Better start using that middle finger!
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Shift + click a color to quickly enter gradient mode. Move your mouse around to quickly preview different combinations.
Satisfied? Select the remaining color to create a Gradient Ramp