Keep your Command Center in the center of your base and defend it as best as possible. Surround it with high level walls and the best turrets available. Start placing walls at the most exposed point, where you have minimum protection. Work your way to completely surround your base with walls. Place all the available towers around them in the areas where there are no walls. Make sure that all corners are covered. Place your Barracks, Rally Points outside this area. Force your enemy to take out Barracks and Worker Huts and other similar structures first, while you take them out with the towers. If you cannot stack all your resource silos in the middle, place the Oil Silos in the best protected area and bait your enemy with the Oil Rig or Gold Mine near some towers. You can also consider placing all your resource silos and resource producing units outside the walls to tempt attackers to spend time on them. However, you will lose a lot of resources as a consequence of keeping your Command Center intact. You do not have to destroy all the attacking troops; just make sure your Command Center does not fall. The alternative is to place all the resource buildings in the middle. Bu doing this, you can counter the strategy enemies who send lots of spies in to attack. If they have no resource building to attack, they will attack random buildings and can be easily be eliminated by your towers. Do not leave open green areas within your base. Create a compact base, and fill empty areas with walls if nothing else is available.