I knew playing as Arabia, coal resources would be in short supply. There are two options, go to war either with the Ottomans, or the Egyptians. From the outset of the game the Ottomans denounced Egypt. So, I sided with the Ottomans over time. Keeping them on my good side while I built up my cities and army. Finally, the Ottmans asked for my support in a war against Egypt. In which case I asked for 10 turns to prepare.
I had two objectives for this war. To gain a seaport on the Mediterranean Sea by taking Alexandria. The second acquire coal, so I can build factories. In the meantime I was purchasing some coal from the Ottomans to supply the factory in my capital at Riyadh.
When the war began, my main army was quite small. I figured I would buildup and reinforce them as the campaign continued. I built two frigates to support the crossing of the Red Sea.
The first objective would be the Egyptian port of Thebes. I began crossing to the south. Landing a cavalry for scouting, 2 GW inf, and a arty. Then I brought over some workers who would build a continuous road to the frontlines. With this force I began bombarding the city. Eventually, I got a second arty in place and began a steady bombardment.
As this was going on, I sent an infantry to the north to cutoff any Egyptian reinforcements that may come from that direction. Realizing the Ottomans had the Egyptian army quite busy in and around Cairo. I decided to send another arty to the north which could help reduce Thebes to rubble.
After capturing and razing Thebes. The next target was the city of Aswan. This fell after a prolonged bombardment. The Egytian army was still busy in the north with the Ottomans, protecting Cairo from assault. The Ottomans were repulsed time and time again. Even though the Ottomans had a serious advantage in technology and numbers.
Once I puppeted Aswan, I began driving for Asyut, in central Egypt. The Egytian army had dealt with the Ottomans enough that they retreated. So, the Egyptian began to bring forces down to defend Asyut. They really stood no chance however, and the city fell after a short brutal battle.
With the fall of Asyut, I rested and refitted my army a bit. My main force had grown in size since the outset of the war. When this was completed I drove on Cairo. This fell too, after some turns. By this time the broken Egyptian army had little fight left. Finally, I got a decent source of coal.
That's it, now it is time to take Alexandria.