Split install guide into 4 pages:

* Preliminary
* eMMC Install
* SDcard Install
* First Start

docs/helios64/install/preliminary.md

@@ -0,0 +1,42 @@
+!!! note
+    Go to [Kit Assembly](/helios64/kit/) to find out how to assemble your Helios64 enclosure kit.
+
+## Requirement
+
+What you need before you start:
+
+**1. microSD Card<br>**
+You need a microSD Card UHS-I with a minimum capacity of 8GB to be able to flash Helios64 image.
+
+We recommend the following models:
+
+- SanDisk Extreme microSDHC UHS-I Card (32GB)
+- SanDisk Extreme PRO microSDHC UHS-I Card (32GB)
+- Strontium Nitro MicroSD Card (16GB)
+- Samsung microSDHC UHS-I Card EVO Plus (32GB)
+
+![Recommended SDcard](/helios64/install/img/recommended_sdcard.jpg)
+
+**2. USB Type-C to Type-A cable<br>**
+![Type C to Type A USB cable](/helios64/img/usb/typec_typea_male.jpg)
+
+**3. Ethernet cable (cat5/6)<br>**
+![Network cable](/helios64/install/img/network_cable.jpg)
+
+
+## Install Options
+
+Helios64 supports two OS installation options :
+
+1. [Install OS on eMMC Flash](/helios64/install/emmc/)
+
+    Recommended if you know already what system setup you need.
+
+2. [Install OS on microSD Card](/helios64/install/sdcard/)
+
+    Good if you want to experiment first and/or test different OS image versions.
+    You will still be able to migrate your OS on eMMC Flash without redoing a fresh install.
+
+**Note:** We will introduce additional install options in the new future.
+
+If you are facing an issue, you can go on the **Armbian** forum to ask for some help. There is a thread dedicated to [Helios64 support](https://forum.armbian.com/topic/15431-helios64-support/).