Update README.md

Author: kaklik

README.md

@@ -4,17 +4,31 @@ This application could be used for testing devices containing standard [RC servo
 
 ## Installation instructions
 
-Install application from [Flipper Zero application catalog](https://docs.flipper.net/apps), or go to the releases, download apps.zip and extract it in your SD card.
+Please install the application from [Flipper Zero application catalog](https://docs.flipper.net/apps), or go to the releases, download apps.zip, and extract it to your SD card.
 
 ## Usage
 
 - Connect the Servo PWM input to **A7** Flipper Zero in.
 - Enable 5V output in the GPIO menu or plug-in USB-C charging cable. (If you're supplying power from an external power source, make sure it has common ground with the flipper GND)
-- Start the ServoTester app
-- Test different servo positions
+- Start the Servo Tester app
+- Move servo required positions using controls bellow
+
+## Controls
+
+| Button | Action                       |
+| :----- | :--------------------------- |
+| 🔼     | Up button increases pulse width by 10 us.|
+| 🔽     | The down button decreases pulse width by 10 us.   |
+| ◀️     | Left button decreases pulse width by 1 us.   |
+| ▶️     | The right button increases pulse width by 1 us..  |
+| ↩️     | Back button exit application.   |
+| 🔵     | Center button change mode. |
 
 ## Build instructions
 
-- Clone the [official flipper zero firmware](https://github.com/flipperdevices/flipperzero-firmware)
-- Add the content of this repo to the `applications_user` folder
-- Follow [official instructions](https://github.com/flipperdevices/flipperzero-firmware/blob/dev/documentation/AppsOnSDCard.md)
+Install [uFBT - micro Flipper Build Tool](https://github.com/flipperdevices/flipperzero-ufbt) to get a toolkit for building flipper zero applications. 
+
+- Clone this git repository
+- cd to *ServoTesterApp* content.
+- run *ufbt && ufbt launch* with flipper connected. It automatically installs the compiled application into Flipper Zero.
+