diff --git a/doc/contributing/building_ruby.md b/doc/contributing/building_ruby.md
index 5aad29ebfe..5d26118577 100644
--- a/doc/contributing/building_ruby.md
+++ b/doc/contributing/building_ruby.md
@@ -85,28 +85,28 @@
         cd ruby
         ```
 
-        Generate the configure file:
+        Run the GNU Autoconf script (which generates the `configure` script):
 
         ```sh
         ./autogen.sh
         ```
 
-2. Create a `build` directory separate from the source directory:
+2. Create a `build` directory inside the repository directory:
 
     ```sh
     mkdir build && cd build
     ```
 
-    While it's not necessary to build in a separate directory, it's good
+    While it's not necessary to build in a dedicated directory like this, it's good
     practice to do so.
 
-3. We'll install Ruby in `~/.rubies/ruby-master`, so create the directory:
+3. We'll eventually install our new Ruby in `~/.rubies/ruby-master`, so we'll create that directory:
 
     ```sh
     mkdir ~/.rubies
     ```
 
-4. Run configure:
+4. Run the `configure` script (which generates the `Makefile`):
 
     ```sh
     ../configure --prefix="${HOME}/.rubies/ruby-master"
@@ -123,7 +123,7 @@
 
 6. [Run tests](testing_ruby.md) to confirm your build succeeded.
 
-7. Install Ruby:
+7. Install our newly-compiled Ruby into `~/.rubies/ruby-master`:
 
     ```sh
     make install
@@ -133,6 +133,41 @@
       generation with different permissions, you can use `make SUDO=sudo
       install`.
 
+8. You can then try your new Ruby out, for example:
+
+    ```sh
+    ~/.rubies/ruby-master/bin/ruby -e "puts 'Hello, World!'"
+    ```
+
+By the end, your repo will look like this:
+
+```text
+ruby
+├── autogen.sh      # Pre-existing Autoconf script, used in step 1
+├── configure       # Generated in step 1, which generates the `Makefile` in step 4
+├── build           # Created in step 2 and populated in step 4
+│   ├── GNUmakefile # Generated by `../configure`
+│   ├── Makefile    # Generated by `../configure`
+│   ├── object.o    # Compiled object file, built my `make`
+│   └── ... other compiled `.o` object files
+│
+│ # Other interesting files:
+├── include
+│   └── ruby.h      # The main public header
+├── internal
+│   ├── object.h
+│   └── ... other header files used by the `.c` files in the repo root.
+├── lib
+│   └── # Default gems, like `bundler`, `erb`, `set`, `yaml`, etc.
+├── spec
+│   └── # A mirror of the Ruby specification from github.com/ruby/spec
+├── test
+│   ├── ruby
+│   └── ...
+├── object.c
+└── ... other `.c` files
+```
+
 [Download Ruby]: https://www.ruby-lang.org/en/downloads/
 
 ### Unexplainable Build Errors
diff --git a/doc/contributing/testing_ruby.md b/doc/contributing/testing_ruby.md
index ca6a991917..4c7ce7f6a8 100644
--- a/doc/contributing/testing_ruby.md
+++ b/doc/contributing/testing_ruby.md
@@ -1,5 +1,9 @@
 # Testing Ruby
 
+All the commands below assume that you're running them from the `build/` directory made during [Building Ruby](building_ruby.md).
+
+Most commands below should work with [GNU make](https://www.gnu.org/software/make/) (the default on Linux and macOS), [BSD make](https://man.freebsd.org/cgi/man.cgi?make(1)) and [NMAKE](https://learn.microsoft.com/en-us/cpp/build/reference/nmake-reference), except where indicated otherwise.
+
 ## Test suites
 
 There are several test suites in the Ruby codebase:
@@ -8,23 +12,23 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
 
 1. [bootstraptest/](https://github.com/ruby/ruby/tree/master/bootstraptest)
 
-    This is a small test suite that runs on Miniruby (see [building Ruby](building_ruby.md#label-Miniruby+vs+Ruby)). We can run it with:
+    This is a small test suite that runs on [Miniruby](building_ruby.md#label-Miniruby+vs+Ruby). We can run it with:
 
     ```sh
     make btest
     ```
 
-    To run it with logs, we can use:
-
-    ```sh
-    make btest OPTS=-v
-    ```
-
     To run individual bootstrap tests, we can either specify a list of filenames or use the `--sets` flag in the variable `BTESTS`:
 
     ```sh
-    make btest BTESTS="../bootstraptest/test_fork.rb ../bootstraptest/test_gc.rb"
-    make btest BTESTS="--sets=fork,gc"
+    make btest BTESTS="../bootstraptest/test_string.rb ../bootstraptest/test_class.rb"
+    make btest BTESTS="--sets=string,class"
+    ```
+
+    To run these tests with verbose logging, we can add `-v` to the `OPTS`:
+
+    ```sh
+    make btest OPTS="--sets=string,class -v"
     ```
 
     If we want to run the bootstrap test suite on Ruby (not Miniruby), we can use:
@@ -33,17 +37,22 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
     make test
     ```
 
-    To run it with logs, we can use:
+    To run these tests with verbose logging, we can add `-v` to the `OPTS`:
 
     ```sh
     make test OPTS=-v
     ```
 
-    To run a file or directory with GNU make, we can use:
+    (GNU make only) To run a specific file, we can use:
 
     ```sh
-    make test/ruby/test_foo.rb
-    make test/ruby/test_foo.rb TESTOPTS="-n /test_bar/"
+    make ../test/ruby/test_string.rb
+    ```
+
+    You can use the `-n` test option to run a specific test with a regex:
+
+    ```sh
+    make ../test/ruby/test_string.rb TESTOPTS="-n /test_.*_to_s/"
     ```
 
 2. [test/](https://github.com/ruby/ruby/tree/master/test)
@@ -54,26 +63,21 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
     make test-all
     ```
 
-    We can run a specific test directory in this suite using the `TESTS` option, for example:
+    We can run a specific test file or directory in this suite using the `TESTS` option, for example:
 
     ```sh
-    make test-all TESTS=test/rubygems
-    ```
-
-    We can run a specific test file in this suite by also using the `TESTS` option, for example:
-
-    ```sh
-    make test-all TESTS=test/ruby/test_array.rb
+    make test-all TESTS="../test/ruby/"
+    make test-all TESTS="../test/ruby/test_string.rb"
     ```
 
     We can run a specific test in this suite using the `TESTS` option, specifying
     first the file name, and then the test name, prefixed with `--name`. For example:
 
     ```sh
-    make test-all TESTS="../test/ruby/test_alias.rb --name=TestAlias#test_alias_with_zsuper_method"
+    make test-all TESTS="../test/ruby/test_string.rb --name=TestString#test_to_s"
     ```
 
-    To run these specs with logs, we can use:
+    To run these tests with verbose logging, we can add `-v` to `TESTS`:
 
     ```sh
     make test-all TESTS=-v
@@ -85,7 +89,7 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
     make test-all TESTS=--help
     ```
 
-    If we would like to run the `test/`, `bootstraptest/` and `spec/` test suites (the `spec/` is explained in a later section), we can run
+    We can run all the tests in `test/`, `bootstraptest/` and `spec/` (the `spec/` is explained in a later section) all together with:
 
     ```sh
     make check
@@ -93,45 +97,40 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
 
 3. [spec/ruby](https://github.com/ruby/ruby/tree/master/spec/ruby)
 
-    This is a test suite that exists in [the Ruby spec repository](https://github.com/ruby/spec) and is mirrored into the `spec/ruby` directory in the Ruby repository. It tests the behavior of the Ruby programming language. We can run this using:
+    This is a test suite defined in [the Ruby spec repository](https://github.com/ruby/spec), and is periodically mirrored into the `spec/ruby` directory of this repository. It tests the behavior of the Ruby programming language. We can run this using:
 
     ```sh
     make test-spec
     ```
 
-    To run a specific directory, we can use `SPECOPTS` to specify the directory:
+    We can run a specific test file or directory in this suite using the `SPECOPTS` option, for example:
 
     ```sh
-    make test-spec SPECOPTS=spec/ruby/core/array
-    ```
-
-    To run a specific file, we can also use `SPECOPTS` to specify the file:
-
-    ```sh
-    make test-spec SPECOPTS=spec/ruby/core/array/any_spec.rb
+    make test-spec SPECOPTS="../spec/ruby/core/string/"
+    make test-spec SPECOPTS="../spec/ruby/core/string/to_s_spec.rb"
     ```
 
     To run a specific test, we can use the `--example` flag to match against the test name:
 
     ```sh
-    make test-spec SPECOPTS="../spec/ruby/core/array/any_spec.rb --example='is false if the array is empty'"
+    make test-spec SPECOPTS="../spec/ruby/core/string/to_s_spec.rb --example='returns self when self.class == String'"
     ```
 
-    To run these specs with logs, we can use:
+    To run these specs with verbose logging, we can add `-v` to the `SPECOPTS`:
 
     ```sh
-    make test-spec SPECOPTS=-Vfs
+    make test-spec SPECOPTS="../spec/ruby/core/string/to_s_spec.rb -Vfs"
     ```
 
-    To run a ruby-spec file or directory with GNU make, we can use
+    (GNU make only) To run a ruby-spec file or directory, we can use
 
     ```sh
-    make spec/ruby/core/foo/bar_spec.rb
+    make ../spec/ruby/core/string/to_s_spec.rb
     ```
 
 4. [spec/bundler](https://github.com/ruby/ruby/tree/master/spec/bundler)
 
-    The bundler test suite exists in [the RubyGems repository](https://github.com/rubygems/rubygems/tree/master/bundler/spec) and is mirrored into the `spec/bundler` directory in the Ruby repository. We can run this using:
+    The bundler test suite is defined in [the RubyGems repository](https://github.com/rubygems/rubygems/tree/master/bundler/spec), and is periodically mirrored into the `spec/ruby` directory of this repository. We can run this using:
 
     ```sh
     make test-bundler