I find these days there are a whole swag of sources for information about any DAW. Here are a few tips I give my sound engineering students to help them learn a new DAW.
Go to the website and download and print off all the information about that DAW. It will amount to quite a few pages. And yes there are things in there you will not have known your software can do. It is a good starter.
Read all the Sound on Sound reviews of that DAW. Reviews are great because they have to cover lots in a short time. I have picked up a lot from these reviews. I had to teach a guy FL Studio once. In SOS there is a review for every version from 4 right up to 10. The first one will often give the main stuff and the subsequent reviews will only cover the additions in the new version. I learned heaps from the reviews alone.
Watch all the videos on the DAW website that relate to that DAW. There are often many many videos to watch. They are great and you learn a lot quickly too. Also there are a lot more on Youtube too. Extra ones from the companies themselves and some amateur ones but all very helpful.
Read any books that have been specifically published on your DAW like Scott's books.
Buy every video that
Groove 3 (and the DAW company itself if they have them) has made on your DAW. These are great and very well made. A must!
The Manual Well this is the scary one. Manuals are sometimes well written and sometimes not but the reality is that a lot of information
is in the manual. If you get stuck open up the manual. 9 times out of 10 you will solve the issue. Sonar X2 has got a beauty. Studio One is good too but not as big but that is a good thing because I can read it completely and I try to do that once a year.
(When I was doing demos for the V Studio 700 system for Roland at one point I read that manual three or four times before I even switched it on! But when I did I was using it as well and as fast as Seth and Brandon. It saved a lot of time. That information does sink in believe it or not) Practice what you have learned. It is the best way. But if you do the stuff above you will be very well prepared to get straight into it!
Have fun.