A tourist is lost in the maze of Manhattan. He goes up to a guy who looks like an authentic New Yorker.
Tourist: "How do I get to Carnegie Hall?"
Scowling New Yorker: "Practice!"
The New Yorker has something there.
Practice, practice, practice. It can't ruin your odds, which are dicey in the first place. Acting, voice, dance. You live and breathe your art. What's another hour you spend, in addition to the 40 you've already spent, learning that German torch song—phonetically.
Make the rounds of small professional and regional theaters. Audition, or look for your next audition, every waking hour. Wait all day for cattle calls where you'll be seen and judged in less than a minute.
Brace yourself for years of rejection and dashed hopes. You're one of legions—no, countless battalions—of performers vying for very few roles.
Network. No place is off-limits. Food truck lines. Supermarkets. Pizza delivery customers. That guy who ordered a large pepperoni with extra anchovies could be that director who casts you for the lead role in Rent.
Climb over everyone you know. Sadly, the road to musical theatrical success is littered with the ghosts of those who didn't make it.
Get a day job. Many gigs you'll be working gratis.
Do all this, and chances are you'll achieve something.