I've gotten a few questions about the Great American Aran Afghan and I think knitters are intimidated. Yes, I think this will probably be the most beautiful afghan I will ever knit and it's a challenge, but it's not that hard. This is what I did before I started:
Learn Basic Cables - There are a few great projects out there for people just learning how to cable. My all time favorite is the Irish Hiking scarf. It's easy enough for someone who's never used a cable needle before and it's long enough to get the rhythm of knitting without looking at the pattern for every stitch. From the same site I would then work on the Besotted scarf. The cables get a little more detailed but it's a nice step up from the first one.
Here's a picture of my Irish Hiking scarf:
This was my first cabling project ever and it looks great. That's what I love about cables! They're not that hard but they look wonderfully complicated. I don't have a picture of the Besotted scarf because that was a gift for one of my close friends.
Learn Seaming Techniques - This one was a bit harder for me because it's more like sewing than knitting. You could do this in a couple different ways. Maybe knit up a simple baby cardigan that requires seaming. Some sock toes are finished by seaming. Or you could just knit up two swatches and practice seaming them together. Whatever floats your boat.
In my case, I found an afghan sampler that I wanted to knit up for my son. It had some easy cables and twists and the patterns helped me get intuitive with my knitting. I will never like seaming but this project taught me that is it pretty important to follow the finished measurements of each square. It just looks nicer when they all line up and it's easier to sew them together. I posted pictures of my finished project of the sampler afghan here.
You really don't have to learn how to seam until all of your afghan squares are completed.
That's about it. I guess it would be helpful if you can read a chart too but they wrote out the patterns line by line so that's definitely not required. If you get bogged down by one of the instructions you can always hop over to Knitting Help for their free videos. I know I did many times until I got the hang of things. Good luck!