If you can, have some low visibility recoveries to your base organised - roads, line features of any kind that you can follow are a bonus, with headings, timings at say 60 kt (low vis type speed) organised.
I haven't done a lot of this kind of thing, but flew in Egypt for some months years ago; having an emergency get-home option was good if you were out and a sandstorm looked like it would encroach.
One other thing that sticks in my mind (pardon the pun) is getting significant main rotor vibes seemingly out of nowhere one day, landing to sort it out and finding a very hard accretion of really fine dust / sand particles stuck to the leading edge. Once we'd removed them (took some work), the vibes were gone.