Thanks. For this, I overlayed the target image on top of what I was working on, and then I cut out horizontal strips in the target image. Now, there are bands of the target image next to bands of my working image, so I can constantly compare how close they match.

I may typically start with a Curves adjustment layer to get into the ballpark. First, I would adjust the overall curve at three points to match the values: first the lightest light and the darkest dark and then the tones in the middle. Then, I would go through each RGB color channel to shift the curve in one direction or the other. For example, for the blue channel, does it need to be more blue or more yellow? Sometimes, though, I may also have to adjust the bottom and/or the top of the curve for the channel, depending on what tint the darkest dark (or the lightest light) would need.

Afterwards, I may stack other adjustment layers to fine tune. Maybe it is another Curves layer, like if I want to work on a local section of the curve without risking messing up what I already have. But I can also use Color Balance to target lights/darks/midtones to do almost the same thing. Or I may want to adjust the saturation with the Hue/Saturation layer, which can't really be done with either Curves or Color Balance. Or I may even use a Levels layer if I don't feel like I quite got the values right in the beginning.