Most of the search damage I've seen from a redesign happened in a single afternoon, and almost always for the same reason: the new site launched without anyone checking what the old one had.
This is the list I work through. It isn't exhaustive and it isn't a strategy — it's the technical floor. Getting it right won't win you rankings on its own. Getting it wrong can cost you the ones you already had.
Before launch
The staging site should be invisible, and the production site should be ready.
- Confirm staging is blocked from indexing, and confirm that block is removed at launch. Shipping a live site with noindex still set is the single most common launch mistake I encounter.
- Give every page a unique, descriptive title. Not the template default, not the business name repeated nine times.
- Write real meta descriptions for the pages that matter. They don't affect ranking directly, but they affect whether anyone clicks.
- Set canonical URLs, especially if the same content is reachable at more than one address.
- Decide on one hostname — with or without www — and redirect the other to it.
- Check heading structure on every template: one h1, ordered h2s.
- Write alt text for images that carry meaning, and leave it empty for images that are purely decorative.
- Confirm the sitemap generates and lists the pages you actually want indexed.
- Check robots.txt permits what you expect and blocks what you intend.
- Add structured data where it genuinely applies — organization, article, service, FAQ — and validate it.
The redirect map, which deserves its own section
If you're replacing an existing site, this is the step that matters most and the one most often rushed.
- Export every URL the old site has. Crawl it; don't rely on memory or the CMS page list.
- Map each old URL to its closest equivalent on the new site.
- Use permanent redirects for moved pages, not temporary ones.
- Redirect to the specific matching page, not everything to the homepage. A homepage catch-all tells a search engine those pages are gone, and tells visitors you didn't care.
- Test the map before launch, then again after DNS has settled.
Anything with inbound links or existing traffic is worth handling individually.
Performance, before anyone calls it an optimization problem
Speed is far easier to protect than to recover.
- Serve images in modern formats, sized for their actual display dimensions.
- Set explicit width and height so layout doesn't shift as images load.
- Lazy-load below the fold, and never lazy-load your largest above-the-fold image.
- Subset and preload fonts; load only the weights you actually use.
- Audit third-party scripts. Chat widgets, tag managers, and tracking pixels are usually the heaviest things on a site and the least examined.
At launch
- Confirm the site is indexable. Check the live response headers and the rendered HTML, not the CMS setting.
- Verify the property in Search Console and submit the sitemap.
- Crawl the live site and fix anything returning a 404 or an unexpected redirect.
- Confirm analytics is recording, and that it isn't recording your own team.
- Check the site on a real phone, not just a narrow browser window.
In the weeks after
- Watch Search Console for coverage errors and crawl anomalies. Some issues only surface once the site is being crawled at volume.
- Compare landing-page traffic against the old site to catch pages that lost their redirect.
- Re-crawl after any significant content addition.
What this list is not
It's a foundation, not a growth plan. None of it will make you rank for something you haven't earned. What it does is remove the technical reasons a search engine might fail to understand or trust a site that otherwise deserves to be found.
Do it once, carefully, at launch. That's far cheaper than diagnosing it six months later when traffic is down and nobody remembers what changed.