Upgrade
One guide per Tabler release with breaking changes. Start from the version you are on and work forward.
Every release that changes something you have to touch in your own code gets its own guide. Each guide starts with a table of the changes that can affect you, then shows a before and after example for every one of them.
Upgrade one version at a time. If you're on 1.4, read the 1.5 guide first, then the 1.6 guide. Releases before 1.5 didn't need a guide, updating the package was enough.
The complete list of changes in every release, including the ones that don't need any work on your side, is in the changelog.

