Or to put it differently - how to keep the highlights from blowing and shadows losing details? I'm mostly interested in what can be done in the field to get me the optimal data to begin with, not during post-processing.
- Use a graduated filter to tone down bright skies
- Take multiple exposures and use a HDR technique to combine them (personally I hate these but that's a taste thing)
- Take your photos at sunrise/sunset when the light is more manageable. I find mornings best as waters are calmer and there are fewer people around etc.
Use a single shot in RAW with HDR techniques. A RAW file has a lot more dynamic range than most people assume. You can get by with simple gradient masks in Photoshop or Lightroom to get decent results.
Note that taking multiple exposures does not equate HDR but rather pseudo-HDR, and can result in difference between exposures (leaves blowing in the wind, people moving around, clouds moving) that need to be dealt with in post.
I use aperture priority mode, spot metering, exposure compensation on +1.5, and do the metering on the brightest area (eg. white clouds). If you don't have spot metering, use centered metering and zoom in on the bright area. You will want to play with different values for compensation to find one that suits your taste (and your subject, and your film or camera sensor).
If shooting digital (JPEG), I can also set a lower contrast, but it's hidden in some menu. This is pointless when shooting RAW. Also, using a low ISO will let you record more contrast.
With all of the above, I only work to protect the highlights; but with slide film and digital, highlights need more protection than shadows. So if highlights are well-exposed, shadows will be as good as they can be.