For shading: Look up tutorials, and learn from them. Watch other artists. Learn the anatomy of what you are drawing. Once you have done those, develop your own style! It doesn't have to be realistic. If you want it to be realistic, you will have to practice...a lot. When I first started realism, my drawings were horrible. Now they are believable!...from a distance. Anyways, practice makes better. :)
I do not know what you are working with, traditional or digital. If you are drawing traditional, use different pencils, and pressures.
For digital, use different styles, brushes, opacities, and techniques. Always use layers.
For lines, that will take practice as well. Consider getting a track pad, or a drawing tablet. If you need help with this, I can draw linearts for you. I find it very enjoyable. X3
If you want a tutorial for digital art, I would be more than happy to make one for you! <3
Winter Month: 3 
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