I’m often asked this question and the answer has a couple of parts. First of all, I advise reading other travel writers widely. The authors of travel books are often the best stylist. You can’t go wrong picking up pointers from Paul Theroux, Jonathan Raban et al. And it’s very enjoyable to read their work for its own sake too! Second, good travel writing prose is no different from any other kind of good prose. There have been many attempts to set out guidelines good writing. Two of them, in particular, are well worth checking out. Each of them dates from the first half of the twentieth century. One comes from the east coast of the US. An Ivy League academic, William Strunk, and a journalist on The New Yorker, E.B. White, produced The Elements of Style. This slim volume offers an excellent basic framework for serviceable prose. Then there’s George Orwell. Orwell worked hard to improve his own prose, because he wasn’t a natural writer. He is the proof there’s hope for all of us. His style pointers are both very brief and very useful. Check them out here: https://sites.duke.edu/scientificwriting/orwells-6-rules/