Meet the sage
He has a big hat, a white beard and a long robe with wide cuffs. His hands rest one on the other, mostly hidden in the cuffs. The robe is so long you can't really see his feet, they're in its shadow. And the light comes from the top right.
RPG or platformer?
This is an RPG character, the kind you see in top-down games. We look down at him a little, so we see the top of his head, or here, of his hat. A platformer character is seen from the side, at eye level, so you only see the very top of the head. Decide the view before you draw.
And don't be shy with proportions. His body is only about two heads tall. Big heads and exaggerated hands or feet give pixel art characters charm. This isn't an anatomy class, just do it on purpose.
Step 1: Outline
Start at the top of the hat with a short line and curve down smoothly: no misplaced pixels, no jaggies, no doubles. Then the wide brim, the shoulders, the long robe down to the feet, the face and the beard, a short line down the middle of the robe, and the arms with their cuffs. The two sides mirror each other, so you can draw one and copy it.
Really, a character outline is simple: a head, a face, two arms and a body. Any doubles you leave now can be fixed later. For now you're blocking out the space.
Step 2: Colors
Fill the robe with the deep orange and the hat with the lighter orange. Draw the beard in white, then fill the face with the skin tone. Recolor the outline around the face in orange so it doesn't look heavy.
Step 3: Shading
Look what shading does here. The character suddenly has volume and reads at a glance. Never underestimate it.
On the hat you'll see a checkerboard pattern. That's dithering: two neighbor colors alternating pixel by pixel, so they blend into each other. The other way to blend is banding, putting the colors in lines one after another. Both are common, but dithering is the classic.
Then think about what blocks the light. The long cuffs cover the hands, so the area under them is a very deep red. The arms stick out from the body, so the lower half of the robe is a touch darker than the upper half. Use the shading colors for the wrinkles, and smooth the edges of the face and beard with a few in-between pixels. Finally, the drop shadow under the robe, in grey. It hides the feet, which is exactly what a long robe would do.
Step 4: Lighting
The light is on the top right, so the right edge of the hat gets white. On the robe, use the lighter oranges, a bit more on the right side. The highlights follow the shape of the body and the direction of the wrinkles, a couple of pixels here, a little zigzag there.
Step 5: Details
The details on this character are just a few spots of anti-aliasing. Three pixels. Sometimes that's all it takes.
Your turn: three more characters
The first three are platformer versions of the sage, in three sizes: we see them from the side, so only the tip of the hat shows. They're simpler than the RPG one you just drew. Try them, and change whatever you like, maybe a different hat color.