How to set up Nikon D80 for outdoor portrait shooting?

You see, the maximum aperture of your lens has been adjusted back two steps, so that's it. Use A mode, adjust the sensitivity when it is too dark, and do not use flash for white balance. Don't set the sensitivity too high, you'd better set it to the lowest sensitivity. That's it. Judging from the question you asked, you may not be good at using a camera. If not, use P mode, adjust the sensitivity and white balance, and try not to use flash. If there is flash, it doesn't matter whether it is used or not.

Because you can't tell where and when to go, it's really hard to say how to adjust. Just like I said, make it universal ... there are different requirements for each kind of light, which is really hard to say.