4. Take stock
You must know what you have in order to understand what must be changed in an IPv6 implementation, and the only way to understand that is to take an inventory. A simple "supports IPv6" checkbox is insufficient; from the feasibility study you should know what IPv6 features must be supported, and your inventory checklist should reflect that.
5. Don't skip the all-important test lab
Setting up a test lab - whether as part of a plan to implement IPv6 or another technology - is important for the safe introduction of new technology into your network. This is true even if your organisation has a small network, or if the network is managed by a service provider. Get the backing of those who sign the cheques by explaining how the test lab would reduce operational expenses, reduce network risk, and increase network up-time and availability.
6. Set milestones and methodologies
Armed with the facts and data from the feasibility study, the inventory, and the results of your lab evaluations, you can establish accurate costs and set a realistic, detailed timeframe for your implementation project.
7. Start now on training
Plan to bring your understanding of IPv6 to the equivalent level with your understanding of IPv4. The good news is that because you already understand IPv4, getting up to speed on IPv6 is not difficult; it's not that different. a training plan that spans a reasonably long time - two or three years or more - can save you money. But again like the overall IPv6 implementation plan, you need to get started now on your training plan.