Update README.md

README.md

@@ -1,2 +1,38 @@
 # xbrightness
 Use xrandr to change brightness when you linux laptop can't use normal way
+
+
+## Usage
+- To shwo current brightnes use `xbrightnes`
+    ```
+    ❯ xbrightness
+    Current: 0.50
+    ```
+
+- To set a brightnes use `xbrightnes <level>`, like `0.5` for 50% or `1.0` for 100%
+    ```
+    ❯ xbrightness 0.5
+    Brightness set to 0.50
+    ```
+    
+- To change current brightnes use `xbrightnes <action><level>` action can be `+` or `-`, like `+0.1` or `-0.4`
+    ```
+    ❯ xbrightness +0.1
+    Brightness set to 0.60
+    ❯ xbrightness -0.4
+    Brightness set to 0.20
+    ```
+
+
+## Installation
+- Requerments:
+    - Make
+    - GCC
+    - Xrand
+
+- Commands to install:
+    ```
+    git clone https://github.com/flifloo/xbrightness.git
+    cd xbrightness
+    sudo make install
+    ```