What is the best non-complicated process to switch CMS without affecting any current rankings?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Stockbridge Truslow: You`re going to affect rankings no matter what you do. - but if you build a solid foundation, get your redirects sorted properly and do everything right, it should improve rankings. At worst, it might hop around a bit and settle back right about where it was.
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  Mal Ö Tonge: if its done correctly and urls are not changed then this should not affect search rankings. Make sure that wordpress it is optimized for speed and then you can copy and paste the content over to wordpress. I would first create a directory for the word...Lihat Lainnya
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  James Fuller: Make sure all the content of the current website is included in the new version. Develop the new site separately. The ranking shouldn`t be hurt even if the subfolders are not identical as long as you include a site map and submit the new url`s/pages in webmaster tools immediately after the new website is launched.If using a template with demo content make sure all the demo content is deleted before launch.Make sure you take advantage of the attachment pages for all media. Don`t leave any section blank and don`t repeat the content. I was able to go from HTML to WP and compete against established websites of competition that have been up for over ten years. My site is less than two years.Make sure to create Google business/merchant listing make sure the business is seen in Google maps and google plus. My website shows in the business/maps listing`s at the top of page one even on key phrases it is ranking well on yet.