About 25 years ago, I solved one for the first time. Now that my kids have one (a Christmas gift), I tried to solve it again. I still remembered the top two layers, but was totally stuck on the third layer.
I found this solution very similar to the one I learned so many years ago. Other sites have pictures and alternate solutions. Of course, YouTube has many demonstrations in case you need to see what is happening.
Cody just got it mixed up so I'll be fixing it again soon.