Step 1: Pick your basic colors from darkest to lightest. I typically use 4. You may use as many as you like. You can hue-shift the colors for a warmer or cooler lighting effect. Step 2: Draw a straight line with the line tool. This is the trunk. For more varied trees, you are free to bend the trunk however you like. Scribble the outline. A rough cone shape is fine for most evergreens. For variation, you can cut in some deeper grooves. No pressure here. You can fix mistakes later. Step 4: Fill in the empty spaces Step 5: Fix up what you've done. You don't want to make anything too point unless it's a dead branch. At the same time, try to add some single-pixel nubs to the edges of your branches. Step 6: Use you're lighter color to draw a variety of blobs. This is the light falling on the exposed branches of the tree. Dithering makes the pine needles come to life. For the "nubs" that stick out of the tree, start with your lighter color on the top half of each and expand back towards the trunk. Remember, trees are super forgiving, so as long as your blobs are organic and not too uniform or evenly spaced, it should look nice. Step 8: Use your darker color to create some rough patterns around the edges of the lighter shapes, smoothing out the hard edges when you can. This will be a lot like step 7. Step 9: highlight. Use minimal color. I'd say I went a bit overboard in this tutorial. Trees are typically much darker than this, even in full sun. Step 10: You are done! BUT: If you want to change your colors and play around with hue shifting, right-click the bucket tool and select the blue paint bucket. This is the color replacer. It will replace all similar colors, so you can easily change the hue of the entire piece.