Walkthrough + Small tutorial!

TUTORIAL/DESCRIPTION BELOW! --Hi! I thought I'd share the way I do things, I hope you guys can get something useful out of this! ^,^ Please excuse the possible grammar errors!
Finished piece -> xdjurax.deviantart.com/art/COM…

Step 1: The Sketch
I always kick off my drawing with a rough sketch which is usually filled with mistakes and anatomical errors. To help me see those better I flip the image horizontally through the process of sketching very often. This is one VERY important part of sketching to me. I only go on with a drawing if it looks at least pretty good turned both ways, though there'll be almost always one stance I prefer, with which I'll continue. I usually have around two or three different sketch layers before I start refining one (i.e. filling in shading lines like you can see in the picture!) Don't worry if something still looks a bit funny, you can always correct that later on.

Step 2: The Base
Just fill that sketch up with a nice, flat color underneath to draw on! I don't worry about coloring in the lines too much, as long as I've got paint wherever I want shading to be, because that way I'll be able to lock a layer on top of that one to do the shading and not have to worry about going all over the place!

Step 3: The Main Shading
This is a very important part of the drawing-I'll be basing most of my further detailing upon this layer. Please make an effort to get those shadows and lights right, because you will greatly profit from it later on and it'll save you time fixing problems. I first go over the base with shadow tones, going from the middle tones to the darkest ones. Use these scarcely and only where needed! Then I apply some subtle lighter tones, and finish with the brightest highlights. Again, use these wisely! You don't want to end up with a plastic shiny pony Also keep in mind that if you're drawing your horse on a cloudy day/dark scene there won't really be any highlights, just the lighter mid tones.

Step 4/5: Detailing
In this step I start going over the main shading layer and smoothen out the hard edges. I differentiate between a hard round brush and textured brush in this step, to make the coat seem more real. I also make my brush smaller and smaller and zoom in more to add details wherever I want them. You can go on with this step as long as you'd like, just remember to zoom out to a 100% and flip your image every now and then to make sure that you haven't gone wrong somewhere!

Step 6: Mane/tail base + Markings
Because the commissioner asked for an appaloosa, this is the step where I'll be adding the base for these markings. I take my time drawing the markings, erasing parts out and adding small dots etc. I play around with different layers and layer settings (opacity, overlay, soft light etc.) until I'm pretty happy with the outcome. I also lay down a base for the mane and tail.

Step 7: Refining + Color effects
Here I make the appaloosa markings blend in better with the coat, making them seem more natural. Because the original shading has kind of fallen away I add some new shading above. I also grab for the smaller brushes for mane and tail, adding some higlights and darker strands in there. On the way I've also been refining the legs more, because they were still left a bit messy.
I then add some color to the coat by using a soft textured brush and (randomly) splashing some color in certain areas. I use goldbrown tones and purpleblueish tones because I'll be adding those in the manes too. I then again play around with different settings of the layers and erase and add wherever I want less or more color. I also add some of these colors around the horse and in the BG, otherwise the transition from horse to BG will become very stark and unnatural-looking.

Step 8: Shinies!
I love this step |D The mane and tail were to look as though they were made of gold and silver. In the earlier steps I've been adding subtle purple/blue strands and goldbrown strands of hair in mane, tail and feathering. Now is the time to really make those light up! I first decide where I want the 'shine' to be by adding small dots of a light color on an overlay layer with a soft round color. Then on another layer I draw a sharper line with a hard round brush in the hair strand that runs through the earlier dot. I repeat this process wherever I want the shine to stand out, but I do make sure that I don't go overboard with the lighting, otherwise it'll just look weird. Again, try out whatever looks nice with opacity and layer settings!

Step 9: Finishing touches
Here I just sit back and look at the things that still aren't good enough to me. I fix the eye, correct the ears, add an additional lock of hair above the eye..I also try if changing the saturation and lighting of the image will make it look better. I then add the small shiny dots in the BG, look over the picture one last time and then it's ready to submit to dA! Though I didn't do it this time I often let the pic rest for a day before returning to it the next day to see if I've missed any mistakes after having looked at it for so long.

Whoop, so that's how I roll drew this horse! I hope it was helpful. There are many ways to do something, this is just the way I currently draw! Also respect if you read all that haha <3