Build tools to help automate simple things you do every day. Build tools just for yourself. That way in a couple years you'll already come to the field with a huge portfolio, and who knows one of your random projects might actually end up getting popular and making you something.
I started making personal projects at 15, worked under my mom's name for freelancing sites while <18 (illegal against their ToS but oh well) and now I'm leading a team of people at a big company since I have 9 years of experience and 5 years of experience with my specialized field (Android).
Just build something.