separate OS with commas

README.md

@@ -31,7 +31,7 @@ gobang means a Japanese game played on goban, a go board. The appearance of goba
 
 ## Installation
 
-### With Homebrew (Linux/macOS)
+### With Homebrew (Linux, macOS)
 
 If you’re using Homebrew or Linuxbrew, install the gobang formula:
 
@@ -47,7 +47,7 @@ If you're a NetBSD user, then you can install gobang from [pkgsrc](https://pkgsr
 pkgin install gobang
 ```
 
-### With Cargo (Linux/macOS/Windows)
+### With Cargo (Linux, macOS, Windows)
 
 If you already have a Rust environment set up, you can use the `cargo install` command:
 
@@ -55,7 +55,7 @@ If you already have a Rust environment set up, you can use the `cargo install` c
 cargo install --version 0.1.0-alpha.5 gobang
 ```
 
-### Using a release binary (Linux/macOS/Windows)
+### From binaries (Linux, macOS, Windows)
 
 - Download the [latest release binary](https://github.com/TaKO8Ki/gobang/releases) for your system
 - Set the `PATH` environment variable