Launch an Ubuntu AMI, in this example I use ami-cef405a7, but check this page to find a suitable AMI from Canonical.
I use a micro instance in this example, but you can use any size.
Copy the following script in the User Data textbox. The script downloads the install script from the earlier blog post and runs it.
#!/bin/bash -ex
exec > >(tee /var/log/user-data.log|logger -t user-data -s 2>/dev/console) 2>&1
# download the install script and run it
cd /home/ubuntu
wget http://dl.dropbox.com/u/6706687/geoserver-ubuntu-ec2-install.sh
chmod 755 geoserver-ubuntu-ec2-install.sh
./geoserver-ubuntu-ec2-install.sh
It should look like this:You can tag your instance or leave it blank.
Use an existing keypair or create a new one.
Use and existing security group or create a new one. Note that port 80 and 22 need to be open for Apache and ssh respectively.
Launch the instance.
That's it! It may take a minute or three to get everything installed, configured, and running even if the console shows that the instance is running.