You can find a more up-to-date version of these tips at my wiki page:
I am a fairly new user of Yii, but I managed to pull through the following steps myself. And since I made a list of these steps for a collegue, I figured I should post them as well. That way, hopefully anyone with doubts of how to learn Yii can use my experiences.
You need to know how to program in PHP. You can find many tutorials on the web, or buy a book. The Basis/Advanced/Database tutorials from w3schools are a good start. Tip: Always use the php.net search function for documentation!
[*]Learn OO PHP
You need to know the basics of how object oriented programming works. Same as above, use Google or buy a book. Click here for a normal tutorial, or a video tutorial.
It is very important to understand what the Model-View-Controller pattern means! If you don’t, you will think Yii is chaos. As soon as MVC “clicks” in your mind, you will see the very logical pattern. Read up on one, two and three.
Visual explanation is the best! So check the screencasts. After that, read up on Larry’s easy tutorial blog.
The Definitive Guide is very helpful! Just walk through all pages from top to the bottom. Tip: Also check out the comments on the bottom of the pages.
Okay, now you should actually get your hands dirty! Either grab the Yii Agile Web Application Development book, or do the Blog tutorial. (Or both!) Note: If you read the book, make sure you check the forums for errata.
There are a lot of good tips in the Yii Application Development Cookbook. Also check out the Yii Wiki and the Yii Class Reference. If you have questions, head towards these forums.
Step 1 & 2 can take days, weeks or years.
Step 3 to 5 takes a few hours
Step 6 takes days, or a few weeks if you’re doing things parttime.