Actually your drawing looks really nice, you even managed to get a good likeness. The issue you are having is "seeing" the values correctly. For example: you rendered the hair dark- that's good- but if you look at the reference, the shadow on the side of his face is as dark as the hair. You rendered it too light. The left eye is almost completely lost in the shadow, but you rendered it much lighter. This is very common with beginners so don't feel bad about it, just make sure you compare the values you are rendering with other values in the image. Hope that helps :)

Steve Huston does teach a robo bean style method to beginners. Bridgman also teaches something similar, just in his own style. What that exercise does is teach you to understand the relationship of the torso to the pelvis. Understanding how the torso and pelvis twist and bend and stretch and pinch is a lot easier to learn with the bean then with a complex figure, that's the point. Soon you'll be adding on to that bean, and your figures are going to feel 3 dimensional and solid.

Wrinkles are like everything else in a drawing, it has to be designed. Just like the body, there are stretch and pinch, a simple side and a complex side. If all the sides are complex, then it loses structure. Also, wrinkles are a chance to establish perspective, if the wrinkle lines go against the perspective, even if that's what is happening in the reference, it will flatten out the drawing. Our job is to leave in what works, and leave out what doesn't. It's all about design.

When doing perspective, it's best to put in all the perspective lines and more importantly, the horizon line. The horizon line makes it possible for you to know if your looking up or down on the scene. All these lines are going to make it easier to know how to make the room look square and not wonky. I did a quick sketch to show you how you should practice your perspective, I hope it helps :)

You are pretty close with this one. The torso looks good, but the pelvis is too complicated of a shape. Try to keep it as a simple box, it will be easier. I like how you were not fooled by the shoulders because they are able to move independent of the ribcage. Keep at it :)

This is a really nice drawing, and I think the perspective is fine. Do beware of ellipsis, you have a couple that could use some work, but overall, this is good perspective. The only perspective issue is the cat, it's too big. If you bring the cat forward, it's almost as big as the bike. One thing I will say is that with drawings this detailed, sometimes there are tangents, or areas where lines can touch other lines and flatten out a shape. Try to overlap the shapes or pull them farther apart to solve that issue. I did a quick diagram to show you what I mean. I wish you success with your mural :)

Didn't post anything in this topic for a while... And I feel the need to get back into it seriously! Here are a few sketches I made directly with a pen. I really like drawing with a pen because I find it a good way to improve the spontaneity of the line. However it's really difficult to keep correct proportions and loose lines. No eraser and no Ctrl Z. But very liberating!

What a lot of people have done, like you, is forget to put in the background value. This is important because it helps you judge all the other values, especially those in the light. Notice the highlights don't pop because they are the same value as the background. If you had included the value for the background, the highlights would be more visible. Having said that, you did a nice job on the pear :)

Hey Arman, I think you are jumping into anatomy and rendering too soon. You should be starting with a gesture drawing, then building the structure to give it 3 dimension, then add details and anatomy and rendering. This will ensure that your drawing is solid before you spend time rendering a drawing that is wrong. I did a quick sketch to show you what I mean :)