Guides
The problems we find most often, what each one means and how to fix it.
Sharing
- How to add a share image to your page
What a share image is, the size to use, and how to set one so your links show a picture when people share them.
- How to set the title and text of shared links
Set the title, description and site name that appear when your link is shared on Facebook, LinkedIn or Slack.
- How to get a large image card on X
What the twitter:card setting does, why links on X can show a small card, and how to choose the large one.
Search
- How to write a good page title
Why the title is the headline of your Google result, how long to make it, and where to change it on your site.
- How to write a page description
What the description under your Google result does, how long to make it, and how to write one people click.
- What a canonical link is and how to set it
How a canonical link tells search engines which address is the main one, and how to fix one that is wrong.
- How to structure your page headings
How to use one main heading and keep the others in order, so visitors and search engines can follow the page.
- What structured data is and how to add it
What JSON-LD structured data tells search engines, which type suits your page, and how to fix a block with errors.
- How to add a working sitemap
What a sitemap does, where search engines look for one, and how to fix one that is missing or does not open.
Accessibility
- How to fix text that is hard to read
What the 4.5:1 contrast rule means, how to check your colors, and how to fix faint text without a full redesign.
- How to mark the sections of your page
How header, nav, main and footer sections let screen reader users move around a page, and how to add them.
- How to name links and buttons
Why icon links and buttons need a name screen readers can announce, and how to add one that matches the label.
- How to write alt text for images
What alt text is, how to describe an image in a sentence, and which decorative images should have none at all.
Security
- Four small security settings for your site
What X-Content-Type-Options, frame protection, Referrer-Policy and Permissions-Policy do, and who can set them.
- How to start a Content-Security-Policy
What a Content-Security-Policy does and how to add one in report-only mode so that nothing on your site breaks.
- How to make browsers always use HTTPS
What HSTS does, what to check before turning it on, and how to raise its time limit without locking anyone out.
Speed
- How to let browsers reuse your files
How Cache-Control lets returning visitors skip repeat downloads, and which settings suit pages, images and scripts.
- How to stop files holding up your page
Why some scripts and stylesheets delay the first view of a page, and how to remove or postpone the ones you can.
- How to make your images smaller
How to resize, compress and lazy-load images, and when to use WebP or AVIF, so your pages load faster on phones.
- What to do when your server is slow
What server response time measures, why 800 ms is too slow, and how page caching, a CDN or a new host can help.