Finding a legitimate is unique because Apple never released it as a free public download. While modern macOS versions are free, Snow Leopard was a paid retail product originally sold on physical DVDs. Official & Legitimate Sources
If you search Google for that exact phrase, you will find hundreds of scam sites offering "fake" DMGs that contain malware or adware. Do not download from "MacDownload.org" or similar pop-up laden sites. Mac Os X 10-6 Snow Leopard Download Dmg
Apple does not provide a direct download for a Mac OS X 10.6 Snow Leopard installer DMG Mac OS X 10
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. Do not download from "MacDownload
Snow Leopard holds a unique place in the Mac ecosystem for several technical reasons:
Before seeking a DMG for installation, ensure your hardware meets the minimum specifications:
Before attempting to install Snow Leopard, ensure your Mac meets the system requirements: