Enable VisualEditor. Read VisualEditor's User Guide.
Log in, uncheck Temporarily disable the visual editor while it is in beta, optionally change Editing mode to Show me both editor tabs, and save your preferences. Or use this sandbox link for testing. Find out how to make links, add or move images, create citations, insert templates, edit tables, and more. Please include your web browser, computer operating system, and Wikipedia skin (usually Vector, sometimes Monobook).
As of 2020, editors at the English Wikipedia have used VisualEditor to make more than 10 million edits.

Welcome to the portal for VisualEditor, a way of editing Wikipedia being developed by the Wikimedia Foundation (WMF) that does not require editors to learn wiki markup. Until VisualEditor, editors had to learn wiki markup to make most edits. VisualEditor will allow people to edit many types of pages without having to learn wikitext, and WMF staff hope that it encourages more readers to become editors.

Even after the eventual anticipated full-feature release of VisualEditor, experienced editors still may prefer editing wikitext because they find it faster and more precise. Editing articles purely in wikitext is and will remain an option that the Wikimedia Foundation has no plans to remove. Even editors who enable VisualEditor will have the wikitext option available from the toolbar for each page and section.

VisualEditor still has many bugs and missing features. If you encounter an issue, you can report it on the Feedback page, but be aware that that page is not actively monitored by WMF staff. WMF staff prefer that you report bugs via the Phabricator bug tracking website.