How to make a color flat map in Photoshop

Quick answer：

To create a color flat map in Photoshop, follow these steps: 1. Open Photoshop and create a new document. 2. Select the 'Gradient Tool' from the toolbar. 3. Choose a gradient style that suits your needs from the options bar. 4. Apply the gradient to your document. 5. Adjust the gradient settings and layer properties to achieve the desired color effect. For more advanced techniques, explore color blending, layer masks, and adjustment layers.