I'd recommend a ruler with the wing's shape of the membrane. That would help the shaky lines even out. Then you wouldn't have to erase so much

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Starters off, if you had more practice with drawing dragons like this, it would be SO much less hard work for you with the shaky lines and everything. Some of it could be the scanner/camera delusions they constantly make, which I hate.
The legs need to be thicker and longer so it matches the right size of the dragon. The way you made the claws should be thicker, also. You should also try making the joints more obvious, as they pretty much just look curved without the joints in the picture. The start of the wing should be more straight instead of those two blobs of it at the start.
The neck is pretty good. It doesn't seem to have any problems that I can see, so that's a plus for you. I guess the shakiness occured with the tail a bit. Try straightening those out and never give up no matter how many times you have to erase. It'll all pull through, I promise
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. The tip of the tail looks a bit wierd, as most dragons have something more detailed and shaped differently, but if that's the style of the dragon, it's just fine.
The wing looks just too much, if you know what I mean. It's a bit big for my eyes and if you made it smaller, that would look better proportioned with the body. The left end of the dragon's wing, is darkened way too much and needs to be lightened. I'm not sure why you did that, but you might want to fix it.
I do like the blending of the colors, though. The spikes are good, perfectly sharp, and the head shape is pretty good.
Keep practicing, and you'll get better
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