The best light of the day is always around sunset or sunrise, when the sun is on the horizon. The light at this time is softer than at normal, and shadows are not that visible. The most noticeable effect of the light around this time is that it is golden. Hence the term "golden hour", which refers specifically to the light right after sunrise and right before sunset. But, is sunrise or sunset better? I'll show you exactly what I do to location scout.
Tip 1: The website Time and Date is my go-to source for sunset and sunrise times. Many photographers also use The Photographer's Ephemeris, which is also pretty good. I simply type in a city or location close to where I will be photographing in Time and Date, and it shows me the times for all the sun and moon events. TPE also does the same thing, but it's more accurate in terms of where you are, since it allows you to tell the specific location via coordinates or clicking on the map.
The Photographer's Ephemermis set to Leigh Lake in Wyoming
As you can see, the sun hits the mountains to the west as it rises from the east. The viewpoint that clicked displayed is on the east shore of the lake. Most photographers would probably aim their camera west, facing the Grand Tetons. At sunrise, these mountains appear to be orange, since the sun is rising behind the photographer at Leigh Lake, illuminating the subject, which are the mountains and lake, front-on. You won't get golden light if the sun is behind your subject, backlighting it. It'll have to be behind you or to your sides.
Tip 2: Use Google Images, 500px, or Flickr to get a rough look as to what the location will look like at the times you are considering to be there. I would strongly recommend 500px if that location is a popular location, since the quality of the images is the highest due to the compression algorithm used, while there might not be that many of the pictures themselves, since 500px isn't a very big site compared to the other two. Google Images has many low quality shots, but there are so many pictures in terms of quantity. Flickr is the most well rounded.
Hidden Lake Sunrise on Google Images
Tip 3: Get there 10 minutes before when you will actually shoot. This is mostly a sunset-late golden hour issue, since the golden hour is right before sunset, but after sunrise. This has happened to me many times. I will get there right as sunset is occuring, and when I find a good location, all the vivid colors and golden glow is no longer there.
One last important thing, is that you will need to make sure your camera has enough battery. Yes, you wouldn't want to get to this excellent location wanting to photograph it under golden light without an opportunity to get a lot of shots. Also, remember to bring enough memory cards.