Apple’s createinstallmedia command did not exist for Snow Leopard. You must use a manual block copy.
Warning: This will erase your USB drive.
Restart the Mac while holding the Option (Alt) key. Select the yellow USB drive.
The original retail disk was a dual-layer DVD. The DMG is a direct rip of that DVD. It is bootable. Do not confuse this with the "Software Update" DMGs, which are only 600MB and cannot install the OS. Mac Os X 10-6 Snow Leopard Download Dmg
1. The "Slimmed Down" Installer
2. Intel-Only Architecture
3. Rosetta (Included, but Optional)
4. Grand Central Dispatch (GCD) & OpenCL
5. 64-Bit by Default
6. QuickTime X & Built-in Screen Recording Apple’s createinstallmedia command did not exist for Snow
7. Exchange Server Support (Out of the Box)
The Internet Archive hosts several DMG files for abandonware purposes. These are not endorsed by Apple, but many retro-computing communities use them. Search for:
Checksum verification: After downloading any DMG, verify its integrity: Restart the Mac while holding the Option (Alt) key
shasum -a 256 SnowLeopard.dmg
A genuine retail copy should have the SHA-256 hash: f984b4c6b3d9e4a6f7c8d9e0a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0