Now if the enemy does try to advance, the narrow bridge will limit the amount of units that they can use at once, while you can surround any unit that reaches your end of the bridge. Not only will this frustrate the enemy, it will keep them occupied while you can safely expand.
Taking cliffs will also give you an advantage, since only one or two units can walk up the pathway, making it impossible to take full advantage of there melee units. It also hurts the opponent since you decide the battles since it's impossible for him to attack because he cant see past the ridges. This is especially useful if you have lurkers which can attack downwards, killing everything that tries to advance up the ramp.
Controlling your units is the key as well. As long as you can surround your opponent, since only a few hydralisks are needed to take out shuttles or wraiths, it will effective cut the map to 1/8 for them, and 7/8 for you. Replenshing lost hydralisks should be done since many skirmishes will occur. Using hit and run tactics to hurt the enemy is also a good strategy. Knowing when to fall back should be obvious, but by this point you will have most of the map, and can generate a huge force. If you do retreat, retreat slowly not all at once, forcing your opponent to slowly advance, instead of letting them gain a huge area. Leaving a few hydralisks will make it harder for your opponent to advance, as opposed to moving all your units.
During the game, you should focus on making sure an air units don't escape unnoticed, and make sure to bring detectors as well. You should be able to win the game easily, since starving the opponent to 1 expansion, is more than enough to allow you to win. However you must still out expand him as well
