README.md in lapidarius-3.2.1 vs README.md in lapidarius-3.3.0

@@ -3,10 +3,11 @@
 * [Scope](#scope)
   * [Alternatives](#alternatives)
     * [gem dep](#gem-dep)
     * [bundle viz](#bundle-viz)
 * [Warning](#warning)
+* [Installation](#installation)
 * [Usage](#usage)
 
 ## Scope
 This gem is aimed to recursively collect the `runtime dependencies` footprint of the specified gem.  
 The output of the library mimics the `tree` shell utility, highlighting the nested dependencies via ASCII characters.
@@ -23,16 +24,22 @@
 
 ## Warning
 Consider only the gems installed on your system are scanned by the library.  
 No remote fetching is performed.
 
+## Installation
+Install the gem from your shell:
+```shell
+gem install lapidarius
+```
+
 ## Usage
 This library invokes the `Gem::Commands::DependencyCommand` class recursively to collect all the levels of dependency.  
 Both runtime and development dependencies are counted (identical dependencies are counted once).  
 Just the runtime dependencies tree is printed to screen:
 
 ```shell
-$ lapidarius --gem=sinatra
+$ lapidarius sinatra
 sinatra (2.0.0)
 ├── mustermann (~> 1.0)
 ├── rack (~> 2.0)
 ├── rack-protection (= 2.0.0)
 │   └── rack (>= 0)