The only thing tricky about getting star metal is getting that meteor shower, in the video below I show you one of the best places too farm it + what overly use on the meteors because they have a shell on these you’ve got to crack off.

So what you will need is:
Fire Orbs (at least 5)
Grease Orbs (at least 6)

or optional if you prefer big explosions:
4-5 Gas Orbs
1 Fire Orb