[Ki-Mono]

First things first, it's always important to understand the animal's legs you want to draw before trying to make it anthro. Two examples I have here is a dog and a cat. Most animals follow similar rules, but always double-check your anatomy! Here is a good visual of the difference between a dog's leg anatomy and ours. The cat structure is virtually the same, so if you nail one it won't be hard to understand the other.

Now to talk about anthro legs:
There is technically no hard and fast rules to anthro legs. Mainly because they don't exist in our real world. So all references to go off of are from other artists etc. So I can only give you my personal tips from my own style and what I observed in others.
Basically the best way to go about making an anthro leg is to create a mash-up of sorts. The top half (from thighs to calves) should be modeled after human legs. The lower half (ankles to toes) should be the animal of your choosing.
The human half is gonna be pretty standard. You're just going to push back from under the knee; as if the person was standing on their tip-toes (plot twist: because they are!). I recommend adding some calf muscles there to add some shape and life to the leg as a whole. When crouching down before a run, the human half will squish as the knee bends.
For the animal half, firstly you need to understand that this half is all foot. Both cats and dogs walk on their tip-toes, so try to keep this in mind when drawing your anthro legs. When the leg crouches down to get ready to run, basically they are lowering their foot. So just pull it back and make it for horizontal (but don't put it all the way down). Some guidelines to work with: the foot should line-up with the knee (to keep center of gravity), and the ankle should be lower than the knee (unless pose demands otherwise). Lastly, practice drawing paws. Your toes are very human-like, which is okay if that's what you're going for, but normally people put paws down there. You can find reference images to practice more realistic paws, but you can do what I do and just draw a lopsided rectangle/triangle, add some lines to it, and call it a day.

Wee thanks for making me draw some anthro stuff! Been wanting to do so for a while now.

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