How do you speed up my site, and how is the speed measured?

  1. First contentful paint (how long it takes to load the first image)
  2. Largest contentful paint (how long it takes to load the largest image)
  3. First input delay (time between clicking something and a response)
  4. Cumulative layout shift (the time it takes for styles to update after resizing). 

All of the above are ways website speed is measured, each one can be optimized in its own way. For example, optimizing images by reducing resolution or size will speed up tests such as the First Contentful Paint test where image loading times are measured. Using Caches in an effective way to store style data is important for speeding up the cumulative layout shift. The first input Delay test is one of the most important tests if it is slow enough the user becomes aware of severe lag issues. The most effective way to improve your score on this test is to avoid overlapping redirects and update links if you remove a page. The Contentful paint tests are similarly important as if images on your site cannot load in time it may lead to a poor user experience as images load in after a visitor to your site has already begun reading, an image loading late may shift the text causing them to lose their place.