What you do with your first raise says more about your future than the raise itself.

Raises are single events, and what you do with one turns into a pattern. If every increase gets absorbed by bigger costs, your income climbs for decades while your situation never does, because spending rises exactly as fast as pay. The first one teaches you which kind you are. Habits set early and quietly, well before the numbers are big enough to hurt.

When the next bit of extra money arrives, decide where it goes before it lands. Move some of it where it cannot be spent casually and leave your spending as it was for a month. Doing that once at seventeen is worth a lot later.