When writing a setting in general you want to really take a slice of time, a moment and really capture the surroundings- the colors, feel, and mood of the setting. The best way to draw people in is to emphasize on the small details and bring them off the page, comparing objects to things having to do with the settings theme. Like for instance: the valley lay bleached and dry, like the discorded skin of a mighty rattler. Here I not only described the look of the valley, but the feel as well, giving it a sense of trouble and danger. However, what if you’re not describing a desert type place, what if it was a lush valley? In this case it might be something like this: The thick vegetation lay like sagging clouds submerging the valley floor. Here unlike the other example the scene depicts a more tropical landscape. The setting shows the reader a valley thick with green life the tops of trees like clouds above the valley floor making a nice canopy.
Now writing a western setting is not much different then writing about any other setting. The main thing that changes are the land types at hand, the feeling you want to portray, and the things we already associate with this type of setting- danger, cowboys, thirst, to name a few. Before getting started something that can help get you started is making a list of all the things that you think of when you think of the “West”.
And so on…
When you make the setting you what you want to do is weave the senses and scenery together.
You want to the reader to be able to identify touch, sound, taste (maybe), smell, and even the thoughts that the setting brings out. The best way to weave the setting is to move from one related detail to another. For example you could be talking about the heat of the sun then go into how it has affected the landscape and from there go into all the dangers in that landscape. These are just ideas and in no way am I saying this is the only way and the best way out there, but I hope that this has opened up some new ideas for you. Good luck in your writing.