Simple answer: You don't.
Long answer: Mac OS 9 and Mac OS X are two completely different beasts. You might have a chance of getting it working if you've a PPC based mac (such as a G5 or G4 based machine) as the Intel ones don't support Classic.
What's Classic? Simple. It's Apple getting a version of OS 9 to run alongside OS X. It's not perfect however and Apple never supported it for long. They removed it from OS X on the new Intel macs purely because it won't run on an Intel processor.
Last but not least, they removed Classic support entirely from 10.5 so you might have a chance if (and it's a bloody big IF here) you've a PPC mac with Classic installed. Even then it may not run.
Long answer: Mac OS 9 and Mac OS X are two completely different beasts. You might have a chance of getting it working if you've a PPC based mac (such as a G5 or G4 based machine) as the Intel ones don't support Classic.
What's Classic? Simple. It's Apple getting a version of OS 9 to run alongside OS X. It's not perfect however and Apple never supported it for long. They removed it from OS X on the new Intel macs purely because it won't run on an Intel processor.
Last but not least, they removed Classic support entirely from 10.5 so you might have a chance if (and it's a bloody big IF here) you've a PPC mac with Classic installed. Even then it may not run.
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Life is like a sewer. You get out of it, what you put into it!
Life is like a sewer. You get out of it, what you put into it!