feat: update README

Author: x1unix

README.md

@@ -1,18 +1,37 @@
 # PowerKey
 
-> - Your password is too long to type or to remember?
+> - Your password is too long to remember?
 > - Try PowerKey instead!
 
+![Preview](./docs/demo.gif)
+
 ## Brief
 
 PowerKey is a simple single-key device which acts as a USB-keyboard and automatically types password, or any another preprogrammed string.
 
+## Building
+
 ### Ingredients
 
-* 1x Arduino Pro Micro.
-* 2x LEDs + 220Ω resistors.
-* 1x Cherry MX or another switch.
-* 1x Button.
+* 1x Arduino Pro Micro
+* 2x LEDs + 220Ω resistors
+* 1x Cherry MX or another switch
+* 1x Button
+* 3D Printer (optionally, to print [housing](./docs/3d-print/PowerKeyCase.f3d))
+
+> [!NOTE]
+> See [include/config.h](include/config.h) for pinout config.
+
+## Firmware
+
+Use `make build` and `make upload` to flash a board.
+
+> [!IMPORTANT]
+> PlatformIO is required to build the project. Install [PlatformIO CLI](https://docs.platformio.org/en/latest/core/index.html) or [VSCode extension](https://marketplace.visualstudio.com/items?itemName=platformio.platformio-ide).
+
+## Housing
+
+You can find a Fusion 360 project [here](./docs/3d-print/PowerKeyCase.f3d).
 
 ## Configuration
 
@@ -24,4 +43,3 @@ See [include/config.h](include/config.h) for pinout configuration and firmware o
 
 Use [PowerKey Programmer](https://x1unix.github.io/powerkey/flasher) web tool to re-program a device and update stored password.
 
-