If you bought Adafruit’s Windows IoT Core development kit, you’ve already got an SD card with IoT installed on it. If so, you can skip this step. But if you don’t have a preloaded SD card, or if you want to install one of Microsoft’s Preview versions, or if you’re just curious, read on for a guide to building an IoT system on an SD card.

To start, you’ll need an 8 GB or larger SD card.

Insert the SD card into your Windows 10 computer so you can format it.
Format the SD card with a single FAT32 partition (if you’re reinstalling Win IoT over an existing system, you’ll still need to do the format!).

There are two ways to install Windows IoT Core. You can install the Core Version, or a Core Insider Preview Version.. The Core Version is Microsoft’s latest stable release. The Core Insider Preview has the latest features, but is a Microsoft testing version. It may be less stable than the Core Version, and it requires a (free) registration with Microsoft to get access to it. The Core Insider Preview Version is for advanced users. If you’re just getting started, stick with the Core Version.

Installing the Core version is easy

Go into the IoT Core Dashboard, and on the left, select Set up a new device. Now select your device type; either Raspberry Pi 2 or Raspberry Pi 3.
Make sure that the correct Windows IoT Core version is selected in the next box. If you selected Raspberry Pi 2, the version box will say “Windows 10 IoT Core for Raspberry Pi 2”.

Insert your micro SD card into your computer, and in the Dashboard, select the card from the dropdown labeled “Drive”. Accept the license terms, and click the “Download and Install” button.
That’s it! The system will alert you when the installation is complete. You can then proceed with preparing and booting your Raspberry Pi.

If you want to install the Core Insider Preview Version

Go to Microsoft’s Getting Started page, and select the type of IoT system you’re setting up.

First, select your board type (we’ll be using a Raspberry Pi 2)
Next, select which sort of IoT system you’re building. We’re starting from scratch with a blank SD card, so select “Flash onto my blank microSD card”
Now, select the Windows 10 IoT Core Insider Preview
Click Next. You’ll be prompted to get Windows 10 and to download the IoT Core Dashboard. If you’re been following this tutorial, you’ve already done this.
Click Next again. Follow the instructions to Manually download and flash a custom image.
You can now proceed with preparing and booting your Raspberry Pi.