Fix osx install doc.

- [x] Remove the brew update entry when installed with binary.
- [x] Add notion of the `.profile` file instead of `.bashrc` (though neither necessarily exists)

Closes #3775.

PiperOrigin-RevId: 170376534
diff --git a/site/docs/install-os-x.md b/site/docs/install-os-x.md
index 091b853..99afc6b 100644
--- a/site/docs/install-os-x.md
+++ b/site/docs/install-os-x.md
@@ -42,9 +42,16 @@
 ```
 
 You are all set. You can confirm Bazel is installed successfully by running
-`bazel version`.
 
-You can later upgrade to newer version of Bazel with `brew upgrade bazel`.
+```bash
+bazel version
+```
+
+Once installed, you can upgrade to a newer version of Bazel with:
+
+```bash
+brew upgrade bazel
+```
 
 ## <a name="install-with-installer-mac-os-x"></a>Install using binary installer
 
@@ -104,15 +111,12 @@
 export PATH="$PATH:$HOME/bin"
 ```
 
-You can also add this command to your `~/.bashrc` file.
+You can also add this command to your `~/.bashrc` or `~/.profile` file.
 
 You are all set. You can confirm Bazel is installed successfully by running
 ```bash
 bazel version
 ```
 
-Once installed, you can upgrade to a newer version of Bazel with:
-
-```bash
-brew upgrade bazel
-```
+When Bazel is installed using the binary installer, updating Bazel is only
+possible by downloading and installing a new release.