Here’s an easy way to draw a custom curve in Photoshop.
1. Click the Curvature Pen Tool
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2. Click where you want inflection points
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3. Drag an inflection point if you need to adjust the shape of the curve
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4. Right-click on the curve click “Stroke Path”
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5. Choose a tool, e.g. Brush
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6. Click OK and see your curve drawn using the existing brush settings
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