readme.md in appium_lib-11.2.0 vs readme.md in appium_lib-12.0.0.rc1

- old
+ new

@@ -19,11 +19,11 @@
 We can avoid the class driver with current `ruby_lib`, but if you'd like to implement your test cases based on instance driver, `@driver`, you can consider using `ruby_lib_core` first.
 
 # Setup
 ## Requirement
 - [Appium](https://github.com/appium/appium#requirements)
-- Ruby: 2.4+
+- Ruby: 2.5+
 
 ### Ruby Lib and Appium
 - Ruby library version over `9.8.0` requires Appium over `1.8`
 - Ruby library version under `9.7.5` can work with Appium under `1.7`
 
@@ -33,19 +33,12 @@
 $ npm install -g appium
 $ appium
 ```
 
 ## Install / Upgrade
-- Update rubygems and bundler
-```bash
-$ gem update --system
-$ gem update bundler
-```
 
-- Install the latest gem release
 ```bash
-gem uninstall -aIx appium_lib
-gem install --no-rdoc --no-ri appium_lib
+gem install appium_lib
 ```
 
 ## [Sauce Labs env vars](https://github.com/appium/ruby_lib/blob/master/lib/appium_lib/sauce_labs.rb)
 
 - `SAUCE_USERNAME` Sauce username