[Ki-Mono]

So this red-line goes with this. I simply decided to make them two separate pieces because otherwise there was just going to be too much going on in one picture lol

Now a huge disclaimer is that there is no right or wrong way to draw a dragon. So these are simply some tips to help your dragons feel more realistic or weighty. This is also just one of an infinite amount of ways I would draw a dragon. I chose this look because I was trying to match it as closely to your original drawing as possible, while also adding a unique flair to it to show you how creative you can get with your designs.

When it comes to bodies, I would use references more from dinosaurs; but various reptiles and birds can work fine depending on the look you are going for. Since this dragon walks on all fours and was big in the middle section, I picked that shovel-billed dinosaur as my muse.
With the head I used a snake for a reference, and the back foot I used an ostrich foot. You'd be surprised how weird various bird feet look and how well they work with dragon concepts if you look hard enough.
Now, dinosaur tails are usually pretty stiff and straight. So I took some creative liberty and made it more flexible and lizard-like. Only thing to keep in mind is the base of the tail and were it attaches to the body. Make sure that it comes from the belly and back, and doesn't protrude awkwardly.

Onto the wings; the first thing you are going to do with any wing (whether it be feathered or bat-like) is to draw an "arm". All wings bend just like ours and have the same basic anatomy. Here is a visual to help. When it comes to a bat wing, you are simply going to make the fingers of the arm very long. There are technically four fingers, but you can get away with just worrying about three, since the forth one is kinda hidden anyways. There is also a thumb which is where you can place your "spike" if you so wish.
After drawing the skeleton, you are just going to add some loose skin in between all the bones. The skin starts in between the arm bones, and ends at the base of the legs. Now, in most media, dragons are drawn with wings that don't extend to the legs. This is totally fictitious and is a style choice. So you can do it in that style, but I personally find it much more difficult to make look "right". Mainly because it technically isn't anatomically correct.
Another side note is that wings need to be insanely large to get a dinosaur like this off the ground. Much larger then what I draw here. When dealing with fiction, this obviously isn't a big deal. However if you really want to push realism, the wings need to monstrously big, or the body needs to be very small and slim. But whether that means anything to you is simply a style choice.

When getting ideas on how to "decorate" and style your dragon, I recommend looking at the Monster Hunter series! There are TONS of beautiful and unique dragon/dinosaur/monster designs that really help to get the creative juices pumping!

Refs: x x x x x x x x

[HyperfixationStation]

ALSO thanks a lot. :>