CONTRIBUTING.md in config-4.2.1 vs CONTRIBUTING.md in config-5.0.0

@@ -1,11 +1,11 @@
 # Contributing
 
 Install appraisal
 
 ```bash
-gem install bundler -v 1.17.3
+gem install bundler
 gem install appraisal
 ```
 
 Bundle
 
@@ -14,16 +14,22 @@
 ```
 
 Bootstrap
 
 ```bash
-appraisal install
+bundle exec appraisal install
 ```
 
+If you need to create new test app for specific rails version
+
+```bash
+bundle exec appraisal rails-7.0 rails new spec/app/rails_7.0
+```
+
 Run the test suite:
 
 ```bash
-appraisal rspec
+bundle exec appraisal rspec
 ```
 
 If you modified any of the documentation files verify their format:
 
 ```bash