Dual Boot Guide [Practical Edition]

Introduction

Previously, I wrote Dual Boot Guide [Overview Edition]. That article was an overview covering topics like "What is dual boot?" and "Why did I choose dual boot?" This time is the practical edition—I'll walk you through the actual steps!

Prerequisites

• A PC with Windows 10 (this guide mainly targets PCs with a single storage drive)
• A USB drive (8GB or larger) for Ubuntu installation
  • This will become a dedicated boot USB, so move any existing data beforehand (it will be formatted before creation)
  • You can format the USB drive again after installation is complete
• Network connection (for Ubuntu installation)

Dual Boot Process Overview

I mentioned this last time, but let me summarize it here too.

1. Create a Boot USB Drive - Put Ubuntu data on the USB to create bootable media for dual boot
2. Partition the Storage (ROM) - Currently only Windows data is allocated on the PC (plus recovery partitions, etc.), so we need to secure space for Ubuntu
3. Install Ubuntu to the Designated Area - Install Ubuntu to the space we secured

Let's get started with dual booting!

1. Creating the Boot USB Drive

Here, we'll create the bootable media for dual boot.

Breaking down the steps:

1. Download the Ubuntu image file
2. Format the USB drive
3. Flash (write) the Ubuntu image file to the USB drive

Let's go through each step.

1-1. Download the Ubuntu Image File

Download the Ubuntu image file from here and save it. The "LTS" after the version number stands for Long-term Support, so you should generally download the one with LTS. (See below for reference) Ubuntu Japanese Team

1-2. Format the USB Drive

As shown below, right-click on the USB drive and select format.

1-3. Flash (Write) the Ubuntu Image File to the USB Drive

Here, we'll use software called Etcher to flash the Ubuntu image to the USB. So let's download Etcher from here. (Download the Installer version here)

Run the installer and just keep clicking through with the default settings.

Once installation is complete and you open it, you should see a screen like this.

Click "Select image" and choose the Ubuntu image file you downloaded in step 1. Confirm that the correct USB drive is selected for flashing, and if everything looks good, click "Flash!"

After about 5 minutes or so, the flashing should be complete.

2. Partitioning the Storage (ROM)

Here, we'll secure space for Ubuntu. Search for "Disk Management" in Windows 10, and when you click on it, you should see the following screen.

Right-click on the C: partition and select "Shrink Volume."

Now enter the size for the Ubuntu partition. I went with about 80GB (adjust this based on your needs).

This should complete the storage partitioning.

3. Installing Ubuntu to the Designated Area

Here, we'll install Ubuntu (prepared in step 1) to the Ubuntu partition (prepared in step 2). Let's go! Breaking down the steps:

1. Shut down the PC
2. Insert the USB drive with the Ubuntu image file and boot into BIOS to change settings
3. Install Ubuntu

Let's go through each step.

3-1. Shut Down the PC

Pretty self-explanatory, haha. Just shut down your PC for now.

3-2. Insert the USB Drive and Boot into BIOS to Change Settings

If you search "What is BIOS," you'll find something like:

Software that controls peripheral devices connected to the computer. It provides means for data input/output to peripheral devices for the OS and applications. Usually, BIOS refers to what is written in ROM on the motherboard or expansion cards, but it can also refer to device drivers provided by the OS.

That's the gist of it. If you just insert the USB drive and power on, you won't be able to boot from the USB contents. That's because the BIOS is currently set to prioritize booting from the PC's internal system. Here, we'll change the BIOS settings to allow booting from the USB drive.

First, let's boot into BIOS. On most PCs, pressing the "F2 key" or "Delete key" while powering on will bring up the BIOS screen. I say "most PCs" because it actually varies by manufacturer. Here's a site with a summary of BIOS boot keys by manufacturer: https://freesoft.tvbok.com/tips/peripherals/bios_boot_fn-key_list.html Also, the BIOS boot key usually flashes briefly on screen during startup (really briefly), so you might catch it there. As shown below, on my PC, it's F1 or Delete key.

Next, let's change the BIOS settings. *Note: You'll mostly use only the keyboard here. First, navigate to the Boot Option section. This is what the current Boot Option looks like.

Select Boot Option #1 and choose the USB drive.

Save these settings and Exit.

3-3. Install Ubuntu

After changing the BIOS settings, reboot. Then you should see the Ubuntu installation screen like this.

Select "Something else" for the installation type, and apply the following settings to the partition we secured earlier.

Execute the Ubuntu installation, and your dual boot setup should be complete!

Conclusion

In this article, I walked through how to dual boot Ubuntu 18.04 on a Windows 10 PC. If you run into any issues with this method, feel free to ask on X or in the comments below.

I share my making activities on X, so give me a follow if you're interested!

References

• Ubuntu Japanese Team
• Dual booting Windows 10 and Ubuntu 18.04