Heh, so, I finally did this one, because I've had some time to draw. And cuz I didn't know what to draw, I decided to do this tutorial for @Nocturna, who asked me to do it!
Anyway, let's get to the tutorial.
I am very sorry for my bad handwriting in advance.
Firstly, you must remember, that wing equals human arm. It has shoulder, forearm (these two are connected with some sort of membrane) and a hand of sorts. Actually, if you want to do a VERY realistic image of human with wings, then you should add another pair of chest muscles under the major chest muscles specifically for wings. Though I think noone does that lol. Think of this just like of a fact or something.
SO! Of course wings start from the shoulder blades. From the top of the shoulder blade I usually draw the top of the wing. Literally it's just a curved line like this one. 1 curve is the elbow, 2 one is the wrist.
*The scheme of the wing*
Now I'll tell you how to draw wings from the back and the front, because front&back differ.
I was drawing groups of feathers from the top row of feathers, which lies on the rest, to the bottom row (I mean that small covering feathers lie on top of the medium covering feathers and etc.)
You can clearly see, that my "feathers" are a stylized "c"s, lol. And "f." stands for "feathers" (just saying)
*wrist/hand not elbow, oops ↓
Now to the front! To draw wings from the front is easier, because here you need to remember only 4 groups of feathers, ahah.
If you thought that "winglets" are a useless group of feathers, then you were wrong, gurl
This is, pretty much, it. I think I told you about everything??? Well, anyway, If you have questions you can always ask me, I will try my best to explain If something seems strange to you.
There are, of course, a lot of other wing tutorials on the Internet, that are better the same, cuz we all draw wings the same way, yeah. Here's the one which I love and actually was using: http://just-a-tid-bit.tumblr.com/post/52368682882/daddystinsoldier-photoshopfornoobs-thoughts