hat questions

[xxmeffiexx.livejournal.com]

Hiya. First time poster, been a lurker for a while now. Unfortunately I don't have any images of my crafts to post. I'm a knitter but I tend to give my projects away.

Some back story before I ask my questions: my favorite aunt is undergoing chemo and has started to lose her hair. She would like something to wear on her head for when she goes out in public. I would like to knit her a hat, or at least make her something to cover her head, but there are some limits...

1. It's June right now, and it's very hot. It needs to be lightweight and comfortable for her to wear.
2. I can knit, but I'm not the best. I can knit a hat, of course, but I'm by no means an expert.

So, my questions: is there a yarn anyone can recommend that can be knit into some type of lightweight hat? Any patterns you would reccomend? If you can think of any other simple suggestions for headgear that would be lovely too.

Thank you all for the help! Can't wait to see what awesome ideas everyone comes up with.