Good question. There are many ways for you to stand out as a student artist these days. I am a retired art educator, not on any admissions committee, but here are my thoughts:
Art Schools and Colleges and Universities rely strongly on portfolios because it is a fair way to compare students and choose a group of students who will do well in their institution. So, please pay attention to the portfolio requirements and make sure you show your best work. Usually, your portfolio will be an admissions committee's first introduction to you and your work. Make sure it is a good one, and one that will make them want to know more about you. As a previous professional mentioned, do your best in your other subjects, demonstrate some extracurricular interests, and find a way to contribute to your community, even if it is not art related.
You can also think about your social media presence and the story you want to tell about yourself. Are you on any social media platforms? Some schools may check these out. I strongly advise you to consider Instagram, (IG), which is the most visual of all the platforms. (Tick Tok is mainly for videos, but IG can accommodate still pictures as well as videos.) I am on IG only for my artwork (and some cats!), and I find it a good way to show what I am working on and what my process it, where I am showing my artwork and so on. It is also a great way to learn about other artists. You might want to include a video of you talking about your work, or demonstrating how you draw, paint of whatever. Pay attention to hashtags and choose some that will connect you to other people or institutions on IG. In that same vein, you might want to review your social media platforms and make sure they do not detract from your story. Get rid of any photos or posts that would put your actions in a questionable light. Focus on your artwork, any volunteer work, trips to museums or galleries, your favorite artists, your other activities, and so on. Despite all your accomplishments, be humble and let people know you are willing to learn and improve your art skills.
As a another previous professional mentioned, get involved in your local arts community. Is there a community non-profit gallery where you live that you could participate in, either by showing your work or volunteering there. Another venue might be community theatre groups, where you could volunteer your art skills for behind the scenes needs. Talk to your art teacher or school guidance counselor for some ideas of what is going on locally and if there are any organizations that might need some artistic help.
Best wishes. I hope some of this helps you in finding the right art program for you.
I feel your body of work will always be your portfolio.
Other people's experiences of your work will aide your portfolio. Have you reached out in your community somewhere and provided (volunteered or sold) your work where people can provide you testimonials of what it means to them? Have you entered any contests? Have you placed or won any contests? What is your art specialty? Are you apart of any associations that specializes in your type of art? Have you presented in a gallery? Have you tried to a collaborative gallery experience with other artists?
Here's my thinking...the artist path is more freelance, and you are always contracting work. The opportunities I mentioned above will help you, hopefully, gain some footing on your journey.
You must create a vision for yourself and your work. This vision will help to guide you and shape your mission.
Hopefully, this is helpful advice to you.
Build social media profiles- LinkedIn, instagram, fb, etc. This would help reach audience that take interest in your work and will show that your appeal to people. Work with folk from the industry- interning is a great way to get some hands-on experience. Additionally, it'll help build your professional network. Hope this helps!
In addition to all the points made already, I'd also add demonstrate your knowledge of and enthusiasm for each school you're applying to. What is it about that school/program that interested you? Is there an artist or artists who studied at that school who you admire? Is there a professor you're excited to study under? Are there course or courses that first drew your attention?
Hope this helps and best of luck to you.