You can either create an EBS Volume from scratch or create an EBS Volume from an existing EBS Snapshot. When you create an EBS Volume, you should carefully consider where it should be created. The first question you should ask yourself is "Where is my instance?" Remember, you can only attach a volume to an instance in the same availability zone. Once you create a volume and specify its location, you will not be able to change its availability zone. To launch a volume into a different Availability Zone you need to create an EBS Volume from an EBS Snapshot.

Create an EBS Volume from Scratch
To create an EBS Volume from scratch, go to Manage -> AWS -> EBS Volumes.
Click the New button.

- Nickname - Specify a Nickname for your volume. You can change the nickname at any time, but it will still be associated with the correct snapshot. NOTE: Amazon will create a unique AWS ID for each volume (ex: vol-6052E7b23)
- Description (optional) - Provide a short description that explains the purpose of the volume. You can change the description at any time.
- Snapshot - Since you are creating a volume from scratch, leave this value as "-none-."
- Zone (required) - Specify the Availability Zone where you would like this volume to be placed. Remember, you can only attach a volume to an instance in the same Availability Zone.
- Size in GB - Specify the desired size of the volume. (The minimum size is 1GB, the maximum is 1TB. One terabyte is 1000 gigabytes, so you the maximum you can enter in this field is 1000.) $0.10/GB per month. See How much does EBS cost?
NOTE: Once you create an EBS Volume, you will no longer be able to make changes to its size or availability zone, etc. You will only be able to change what's inside the volume.
Click Create.