Flexbox Starter Kit
First up: Flexbox Froggy
Honestly, this is the best introduction to flexbox I have found yet. It runs through all the relevant properties and gives you a chance to see them in action which is essential because just reading through a list of them can quickly become overwhelming. Plus it’s all dressed up as a cute game of frogs. What more can you want?
Everything else: CSS Tricks Guide to Flexbox
Everything. The CSS Tricks guides are always good and the flexbox one is no exception. However, reading it with no prior knowledge can be confusing if you are trying to do something even a bit more complex than a standard row of images. But it’s the perfect follow up to Flexbox Froggy and if I run into any problems, it’s generally the first article I refer to.
Guide to Properties
Exactly what combination of flexbox properties to use is often my biggest challenge and I sometimes end up experimenting until I find the right one. This handy visual guide can help with that and you can experiment away right in your browser.