Hidden In Plain SightThe Hejaz Railway - Scout The Crash Site.
Simply get out your binoculars when the mission starts and look around the entire crash site.
The Bedouin - Find the book without being detected.
Simply use the pull and melee combo by using your shell casing to lure enemies towards you or apart and you will be able to knife them. The one you need to watch however is the sniper on top of the cart so lure everyone away from him and leave him for last.
Celebrities - Collect all field manuals.
0:00 - Field Manual 1
0:40 - Field Manual 2
1:05 - Field Manual 3
1:40 - Field Manual 4
2:25 - Field Manual 5
Young Men's WorkGertrude Bell - Kill one of the officers by using a Bolt - Action rifle.
From your spawning area, head over to the weapons depot and inside a tent is a silenced sniper. Inside the building you will find the officer you need to kill so sneak in and headshot him.
T.E. Lawrence - Kill one officer with a melee attack.
When you reach the village you will find the officer inside the building overlooking the radio station. Sneak in and melee him.
Tanks In The Desert - Kill one of the officers by using a tank.
Head over to the ruins now and you will be able to grab one of the two tanks. When inside a tank enemies don't notice you so drive around and look for the general who will be with a Juggernaut by his side and blast him.
Women Rise - Collect all field manuals.
0:00 - Field Manual 1
0:35 - Field Manual 2
1:40 - Field Manual 3
2:20 - Field Manual 4
2:50 - Field Manual 5
Hear The DesertDesert Cars - Destroy the three vehicles while undetected.
Very easy if you still kept that sniper from the previous mission (the silenced one). From where you spawn, snipe all the enemies that you see aside from the juggernaut and let them find the bodies (this doesn't cause alert just makes enemies walk around more). When there is only the juggernaut left, run around and find some dynamite in chest's and throw one on each car then just hit the trigger and it'll unlock. I will post my walkthrough showing it off when it's uploaded.
Planes above the sand - Keep at least 2 field guns operational.
The best way to do this is to not touch a field gun but rather find the sniper which does massive damage to vehicles inside one of the weapon tents and run around the map. This will cause the train to aggro on you and not the guns.
Guerilla Warfare - Collect all field manuals.
0:00 - Field Manual 1
0:20 - Field Manual 2
0:45 - Field Manual 3
1:10 - Field Manual 4
1:35 - Field Manual 5
Arab Revolt - Finish the nothing is written campaign.
simply watch the final cutscene and that's it.