Steve Lesem, President and CEO of Mezeo Software (www.mezeo.com), says:

Identify a use case before starting.
A common mistake that we see is the extraordinary focus on the technology as opposed to a focus on your cloud storage use case and the business case that surrounds the use case. The project should start with an analysis of the use case and it’s resulting impact on the business, and operate on the assumption you can source a cloud of appropriate size, scalability and costs.

Research technology solutions that are most appropriate for your use case.
When you take the use case approach, you will quickly understand that a private cloud is not just a storage infrastructure, but an ecosystem of cloud storage clients, backup and archive solutions, special purpose data movers, management and support, that, when combined with a cloud storage infrastructure gives you a complete solution. Once again, use case focus will flush this out, versus a platform technology led process.

Integrate cloud storage with your overall cloud computing strategy.
A storage cloud is simply one layer of a cloud computing stack. How does this cloud fit within your cloud computing stack? Does the way in which you integrate it support the other cloud computing decisions you have made? Evaluation of the cloud storage solution and how it will interact with, support and/or be the infrastructure associated with your overall computing cloud is a critical part of your overall evaluation. You may also choose to use a service provider hosted “private cloud” to solve issues associated with your deployment, and not ever deploy the storage part of a compute cloud within your own data center.