Lightning Flow Tutorials
These tutorials feature the new Flow Builder that’s coming in Spring ’19. (If you don’t have Spring ’19, you can get a free preview release here.)
These are designed to work well both as an introduction to Flow for someone who has never used it and as an introduction for someone converting from Cloud Flow Designer.
More Flow Resources
Flow Documentation (https://sfdc.co/flowdocs)
Lightning Flow Developer Center (https://sfdc.co/flowdev)
“Unofficial Flow” Community Site (lightningflow.net)