Reduce the opacity of the layer to 50%. You can do this by going to the "Opacity" field near the top of the "Layers" palette, clicking on the down arrow and dragging the slider left to 50%.



I am going to change the foreground color to red by first double-clicking on the foreground swatch and picking a shade of red.

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Select the "Brush" tool by clicking on the brush icon in the toolbar, 4th one down on the right or just press the "B" key.

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With the "Brush" tool selected, go up to the info bar and click on the down arrow in the "Brush" field and select a brush. A soft, round brush will do fine.

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