Command & Conquer 3: Tiberium Wars/Steamrolling

In my opinon, a steam rolling strategy would include a constant flow of new units to the battle. You will have to have a strong economy to keep the units flowing. Also, don't be scared to retreat units. Losing half of your army is always better than losing the whole army. If you prefer tanks (most steamrolling tactics use tanks), then having two war factories would be beneficial to you. With that said.

A strategy that I like, and it involves GDI, includes the rig. Start off with your basic deployment, power plant, refine and then straight to war factory. after the war factory is built, pump out one harvester while you are now building the communication center. once that is built, build one rig and roughly 2-3 predators. You could also include some rifle squads to prevent infantry spam (4-5 should do the trick.) You will have to scout and if the area is clear, move the rig (supoprted by the tanks) as close to the enemy base as possible (it helps if the guardian cannons can attack structures or even harvesters.) While the attack is happening, more harvesters and refineries are necessary for a strong economy. During the intial assualt, try to keep the preds inside the repair range of the rig. Have your infantry set up fox holes and then proceed to reinforce. For this to work properly, you have to be quick at getting your structures built and units into the battle.