Time and practice, love <3 It took a little while for me to get off the ground, too, so don't be discouraged. :) You're off to a beautiful start!
I'll offer a little critique that you can try out, though. Feel free to message me if you have any questions!
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If I were to make a guess, I'd say perhaps you're smudging the horse a little too heavily during body prep. The lines along the back aren't super clear, and the light rays are a little strong.
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I will also gently point out that the outlining around the horse should be where the light is touching it (so not on the hooves, and wouldn't be visible on the white <3) and then there'd be a shadow down there.
Morning Showers then Cooling
