I would recommend saving up $300 - $500 and getting a secured credit card. When my sister turned 18 she had zero credit, applied for a secured cc and was approved. She used it for a year, making all her payments on time. 1 year later she applied for a "regular" rewards credit card, was approved and now routinely gets offers for $5k - $10k cc's.
Most local banks and credit unions offer secured credit cards. You'll get back your deposit + interest earned after you close your account.