Investing as a highschooler

18f, senior in highschool about to graduate this summer. I recently started putting my money into index funds monthly, with my father matching 100% of whatever I choose to put via Robinhood (he owns a custodial account, so it's under my name and will be in my possesion once I hit 21). Currently, I'm putting about $250 monthly (with his matching it's $500 total) and splitting it using this plan: QQQ (40%)- $200, VTI (24%)- $120, VXUS (20%)- $100, SCHD (16%)- $80 Any tips for beginners? Mistakes t