Hey Kilo!
I'm excited about you interest in designing. First thing i would suggest is working on your sizing and placement of your focal. She is really small in the space and is oddly placed. In vertical sigs it's kind of hard to do placing, or at least it is for me.
One thing you want to keep in mind is your Rule-of-thirds. The rule suggests that an image should be imagined as if it were divided into nine equal parts by two equally-spaced horizontal lines and two equally-spaced vertical lines, and that important compositional elements should be placed along these lines or their intersections.
(If you need further help understanding rule-of-thirds, let me know and i'll try to dig up an old post of mine where i spent some time explaining it.)