diff --git a/src/arm-ubuntu/README.md b/src/arm-ubuntu/README.md
index 42d782d..d5dd071 100644
--- a/src/arm-ubuntu/README.md
+++ b/src/arm-ubuntu/README.md
@@ -49,11 +49,11 @@
 ## Building the disk image
 
 This requires an ARM cross compiler to be installed. The disk image is a 64-bit
-ARM 64 (aarch64) disk iamge. Therefore, we only focus on the 64-bit version of
+ARM 64 (aarch64) disk image. Therefore, we only focus on the 64-bit version of
 the cross compiler. It can be installed by:
 
 ```sh
-sudo apt-get install aarch64-linux-gnu-g++-10 aarch64-linux-gnu-gcc-10
+sudo apt-get install g++-10-aarch64-linux-gnu gcc-10-aarch64-linux-gnu
 ```
 
 In order to build the ARM based Ubuntu disk-image for with gem5, build the m5
@@ -99,6 +99,18 @@
 
 # Booting the disk image using QEMU
 
+## Generating an SSH key pair
+```sh
+ssh-keygen -t rsa -b 4096
+```
+Leave all prompted fields empty and hit enter. This will generate a public and
+private key pair in files `~/.ssh/id_rsa` and `~/.ssh/id_rsa.pub`. If your username
+is different from what is printed by command `whoami`, then add `-C "<username>*<hostname>"`
+to the command:
+```sh
+ssh-keygen -t rsa -b 4096 -C "<username>*<hostname>"
+```
+
 ## Making a cloud config file
 
 First, we need a cloud config that will have the authorization information
@@ -120,12 +132,14 @@
 ```
 
 * Note: Do not leave stray spaces in the `cloud.txt` file.
+* If your username is different from what is printed by command `whoami`, then use that for parameter "name" in cloud.txt
 
 More information about generating an ssh rsa key is available
 [here](https://docs.github.com/en/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent#generating-a-new-ssh-key).
 You can ignore the GitHub email address part.
 
 ## Booting the cloud disk image with the cloud config file
+In the `arm-ubuntu/disk-image` directory,
 
 ```sh
 dd if=/dev/zero of=flash0.img bs=1M count=64
@@ -150,15 +164,19 @@
 
 ## Manipulating the disk image
 
-While the qemu instance is still running, we will use Packer to connect
-to the virtual machine and manipulate the disk image. Before doing that, we
-need to add the private key using `ssh-add`.
+When the qemu instance has fully booted, cloud-init has completed, and while it
+is still running, we will use Packer to connect to the virtual machine and
+manipulate the disk image. Before doing that, we need to add the private key using `ssh-add`.
 
 ```sh
 ssh-add ~/.ssh/id_rsa
 ```
 
-This process is automated. In the `arm-ubuntu/disk-image/` directory,
+If the image was booted in qemu on a port number other than 5555, edit the `ssh_port`
+parameter in `arm-ubuntu/arm-ubuntu.json` accordingly. The disk manipulation
+process is automated. If your username is different from what is printed by
+command `whoami`, then edit `build.sh` and change the value of `USER` to `"<your_username>"`.
+Then in the `arm-ubuntu/disk-image/` directory,
 
 ```sh
 chmod +x build.sh
diff --git a/src/arm-ubuntu/disk-image/arm-ubuntu/cloud.txt b/src/arm-ubuntu/disk-image/arm-ubuntu/cloud.txt
index 4d22189..4eb2627 100644
--- a/src/arm-ubuntu/disk-image/arm-ubuntu/cloud.txt
+++ b/src/arm-ubuntu/disk-image/arm-ubuntu/cloud.txt
@@ -1,6 +1,6 @@
 #cloud-config
 users:
-  - name: ### insert the username here ###
+  - name: ubuntu ### change this name to the current user (use `whoami`) ###
     ssh-authorized-keys:
       - ssh-rsa ### insert the rsa key here ###
     sudo: ['ALL=(ALL) NOPASSWD:ALL']
diff --git a/src/arm-ubuntu/disk-image/build.sh b/src/arm-ubuntu/disk-image/build.sh
index 86332d2..bea8905 100644
--- a/src/arm-ubuntu/disk-image/build.sh
+++ b/src/arm-ubuntu/disk-image/build.sh
@@ -27,7 +27,7 @@
 
         count=`grep "name: ubuntu" arm-ubuntu/cloud.txt |wc -l`
         if [ $count -ne 0 ]; then
-            echo "cloud.txt is not modified correctly! Please refer to the README.md file on how to modify name and ssh-rsa in the cloud.txt file."
+            echo "cloud.txt 'name' is not modified correctly! Please refer to the README.md file on how to modify name and ssh-rsa in the cloud.txt file."
             exit
         fi
 
@@ -38,7 +38,7 @@
         if [[ "$KEY" == *"$USER@$HOSTNAME"* ]]; then
             echo "cloud.txt verified!"
         else
-            echo "cloud.txt is not modified correctly! Please refer to the README.md file on how to modify ssh-rsa in the cloud.txt file."
+            echo "cloud.txt 'ssh-rsa' key is not modified correctly! Please refer to the README.md file on how to modify ssh-rsa in the cloud.txt file."
             exit
         fi
     fi