Overall, the Terrans have an advantage over the Protoss but not in the beginning though!

- Build many bunkers in the beginning. Fill each bunker with 3 marines and one firebat. This is done to prevent a rush of Zealots which can really devestate you.

- Once enemy Dragoons come into the picture, you'll need better military. Get siege tanks and vultures. You may also wanna research Spider Mines and Siege Mode.

- Protect your siege tanks against upgraded Zealots!! They can take out siege tanks with great ease, so you'll need firebats to back your tanks.

- Overall, you should play quite defensively in the beginning unless you can tell that your opponent won't rush.

- Missile Turrets can spot cloaked units and hit air units which can really make a curious Protoss player frustrated. (They can't get Observers safely into your town.)

- Go for Battlecruisers and research Yamato Cannon. It has a high range and can do massive damage for only 150 mana. Useful when taking out Photon Cannons.

- Remember to get EMP Shockwave for SCI vehicles. This can disable Protoss shields which is utmostly essential to any Protoss player. You'll be able to destroy their units easily now.

- Research Lockdown for Ghosts; it's useful against Carriers, Arbiters, and other robotic Protoss units. Units affected with Lockdown won't be able to move for a while.