By road: from UAE
U will go using coast road to Al Seeb ( see the map) and
then cross to Nizwa city.
Tip: 1- This cross is risky road for about 100-150 Km between mountains and it is a single road and I recommend not travel in this road by night.
Tip: Using Hatta entry point will add about 100 Km more to the way to Salalah
Tip: This road is more enjoyable up to Nizwa .
Tip: The distance between Hatta and Al seeb is a highway
U will cross the desert direct from Al Biraimi to Salaah one way.
Tip: There is only one way from Nizwa to Salalah through the desert
Using the Bus: 1- U can take the Bus from Dubai to Muscat-Salalah Dh 360 (round trip)Tip: take care because there small areas of broken (asphalt) in middle between Nizwa and Salalah. U can get them between the wheels.
The last 70 Km before Salalah is a mountain area which is full of fog any day of the year and anytime of the day and U will find cattle crossing the road every now and then so,. I recommend to drive this part of the road when unexhausted and at daytime to minimize risk.