Perspective is way off in so many places, the pose isn’t executed well and the colors of the grass/sky are too flat. those are the 3 biggest issues i’ve noticed.
I’m always open for criticism, so if you’re reading this, please tell me what I could improve on the most! :D
Name your layers, when you start using them. It makes life so much easier :)
Even a bit of shading on the ground can help a lot with placing a character on a surface – as you’ve already done.
Trees can sometimes be made realistically by drawing scraggly branches somewhat randomly reaching out (non-straight lines) and forking. My mother encouraged me to trace individual branches out on a tree with my eyes (and draw out some semblance of their style in pencil and paper); one can then add foliage on in clumps or patterns, to give an example of one approach. There are many ways of drawing trees; one only needs to know one or two to get satisfying results to begin with.
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