Snowflake is available in Tor Browser stable for all platforms: Windows, macOS, GNU/Linux, and Android.
You can also use Snowflake with Onion Browser on iOS.
If you're running Tor Browser for desktop for the first time, you can click on 'Configure Connection' on the start-up screen.
Under the "Bridges" section, locate the option "Choose from one of Tor Browser's built-in bridges" and click on "Select a Built-In Bridge" option.
From the menu, select 'Snowflake'.
Once you've selected Snowflake, scroll up and click 'Connect' to save your settings.
From within the browser, you can click on the hamburger menu ("≡"), then go to 'Settings' and go to 'Connection'.
Alternatively, you can also type about:preferences#connection
in the URL bar.
Under the "Bridges" section, locate the option "Choose from one of Tor Browser's built-in bridges" and click on "Select a Built-In Bridge" option.
From the menu, select 'Snowflake'.