I find that the hardest part for me is the parts where you have to knit for $inches. That seems to always be the part where I have the most trouble keeping my focus. If I know I have x rows left then it's a bit easier.
Anyhow, I finished the scarf and I'm really happy with how it looks. Huge thanks to my husband for being willing to go stand in the sun in 90 degree weather while I drape wool around him and take pictures.