Add docs for cloning and building ports in readme.
- [Abstract](#abstract)
- [Table Of Contents](#table-of-contents)
- - [1. License](#1-license)
+ - [1. Build System](#1-build-system)
+ - [2. License](#2-license)
<!-- /TOC -->
-## 1. License
+## 1. Build System
+
+Follow these steps to build and install **METACALL** manually.
+
+``` sh
+git clone --recursive https://github.com/metacall/ports.git
+mkdir ports/build && cd ports/build
+cmake ..
+make
+make test
+sudo make install
+```
+
+## 2. License
**METACALL Ports** is licensed under **[Apache License Version 2.0](/LICENSE)**.
