Following are some good practices for creating custom content element types and plugins and for customizing content elements for usage in the backend.
- Use a sitepackage extension to maintain your site customization (such as backend layouts, custom content elements etc.)
- How you structure your extensions depends a little on the use case and if they will be resused in several projects and / or made public. If you create one extension for every custom content element, you may want to think about whether they might be merged into one or more extensions.
- Do not use deprecated functionality. Read the Core Changelog to check for deprecations and breaking changes between TYPO3 versions.
- Some naming conventions are described in the chapter Naming Conventions.
- Read (or skim) the Coding Guidelines.
- Make it easier for your editors by hiding the following by
- content elements that should not be used in the "Content Element Wizard"
- fields that should not be filled out in the backend forms.