Many friends said they want to know how i do it. Making a tutorial, for me, is like asking a magician of his magic tricks. Then he would answr, "A magician never reveals his secrets." It's the same feeling for everyone i'm sure. Sometimes i don't want to share it, for the fear of someone copying my style (w/c is expected).

I was told, as a beginner, it's alright to copy. Don't we all? In Advertising, it's the same. We copy because we like what we see. But your goal should not exceed greater than who you're copying from. Like when copying ur seatmate's answers (i know we do it anyway), make sure you change the answer to ur own. Your goal is to be your own person, find ur path. CREATE YOUR OWN STYLE! BE DIFFERENT! You'll be surprised..

So i'll make this tutorial because many of my friends want to be someone. I'm simply helping them! So in return, all i ask is to help me make u better than you were before. Here's my know-how on Digitally Airbrushing!

Lineart by: Studio Cutepet - Anime CG. [link]
Coloring Tuturial by: Your truly. Arigatou to Cutepet studio for teaching me everything i know now!

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KASAI's AIRBRUSH TUTORIAL: Mewpen (read this if u can't see the above text)

STEP#1 You MUST have an image. Be it sketched and scanned or digitally inked (many have grown fond of the mouse-pen/tablet).

STEP#2 CLEAN UP. My weapon? The brightness/contrast in the Image>Adjustments to clean my pencils away. Using the same amount of 10% Brightness and 30% Contrast all the time. But you can adjust this for your own intentions.
Sometimes u can switch ur colormode to gray scale to do this w/o distractions, then switch back to RBG mode when u want to start coloring.

STEP#3 LAYERING. Using layers are important, this is to keep track of everything ur doing. Naming them is a must! So u know what piece ur working on.
Most beginners should start plenty using seven to ten layers (or more): skin, skin shade, hair, hair shade, hair highlights, clothes, clothes shade, extra (eyes, mouth, special FX), background (already fixed).
I use my usual magic SIX (in this order downward): lineart, extra, hair, clothes, skin, background.
But for now, i'll start you w/ Ten layers. The more the lot you learn. hehehe!

STEP#4 SELECT the Lineart layer, then using the magic Wand (usually at 32%, anti-aliased), select the area you want to color 1st (for me, i start w/ skin). You can check if you got all of it by using the "Quick Mask mode" pressing a shortcut key "Q". The one you've selected will appear in white, pink otherwise. Pressing "Q" again will return to ur normal mode. Keep doing this often to check missed areas.

STEP#5 We'll start coloring w/ 1-TONE 1st. it's important doing this technique before adding shades, coz' it will help you decided what colors you want to use.
Once you've selected your desired area (under Lineart layer), select the Skin layer, choose a color then Fill it (either w/ the paint bucket tool or Edit>Fill).
Repeat steps 4 and 5 for the other layers till you've completed coloring your Single tones, this including the background. To help you avoid confusion, your background color should be the opposite color of your subject (ex: if ur subject is mostly in red, bg should be in green or blue).

STEP#6 If you like your choice of COLORS, then that's good! If not, select the layer you want to color-change, go to Image>Adjustments, choose either "Color balance" or "Replace Color" and simply fiddle with the Color level arrows till u get your desired color.

STEP#7 SHADING. YAY My favorite part! In coloring you should know the basic of shadow and light. For me, i simply half-close my eyes and imagine where i want to put the light.
Choose the layer you want to shade 1st (skin again for me) by holding the Ctrl button and selecting ur layer's image in the layer. This automatically selects ONLY that layer. My easy way to fast magic wand! Hehehehe!
Then using the Medicine dropper, get the skin color and change it to a darker shade. Make sure ur on the skin LAYER and that ur skin is SELECTED.

STEP#8 BRUSH TOOL. Let's use the Airbrush (the soft gradient one). With ur dark color picked, ur skin LAYER selected and the empty skin-shade LAYER highlighted, color away! Change ur brush size once in a while to get every area. If you don't know that much of shadows yet, you can just color on one side. It helps!
Make sure you often zoom on small areas so you won't miss a spot. You can now add darker tones and possible lighter ones.

STEP#9 Follow step8 with the other layers. But don't forget to keep track of what LAYER you're on. Make sure ur on the RIGHT one when coloring! Skin layer selected (w/ magic wand), skin-shade layer highlighted (in the layers). Hair layer selected, hair-shade layer highlighted. Clothes layer selected, clothes-shade layer highlightened ... and so on. Be creative when coloring!!

STEP#10 SPECIAL FX and BACKGROUND. I created a design on her t-shirt. To do this, select ur clothes LAYER (not clothes_shade layer) w/ the magic wand and make a new layer above it. Name it "Special" or "Clothes_FX". Use a special brush and pick a darker or lighter color (anything to contrast the shirt), and play w/ imagination by clicking here and there. Change the opacity to blend w/ the shirt. There u got a design!
For a background, aim for simplicity. Using elements of design: Line, shapes, value, balance etc..

STEP#11 uh... no step#11.. ur done! YOSHA!!

A little note: Doing Cel-shade is the same process only instead of the airbrush, either you use a different kind of brush (the solid one) or the Pen-tool. But that, my friends, is tutorial history! Have fun!!