Hobbies And Interests
Stay Low
The most basic and easiest-to-follow stealth tip in the game is to stay as low as possible when around enemies. Standing up and sprinting around is about as effective as screaming "over here" when trying to stay stealthy. You should crouch whenever enemies are present and crawl when enemies are close.
Move Slowly
The more slowly Snake moves, the less noise he makes. It helps to move as slowly as possible when sneaking around. However, moving too slowly may leave Snake exposed in a particular spot and alert enemies. You can tell how appropriate your speed is by looking at Snake's gauges. If enemy alertness spikes, you're going too fast; you can go faster if enemy alertness is stationary.
Tranquilizers
The tranquilizer weapons are almost a cheat for stealthy players. You receive tranquilizer weapons in the middle of the first act. Instead of killing enemies, tranquilizers temporarily faze them. If an enemy is blocking your stealth path, you can shoot her with a tranquilizer to knock her out so you don't have to worry about her detecting you. However, you should be cautious when using tranquilizers on groups of enemies, because shooting the first one will alert the others and you may not be able to shoot the entire group fast enough.
Watch Your Gauges
Snake's various onscreen gauges can help you detect elements that can disrupt your stealth that you might not be able to identify. You may not be able to see an enemy that is obscured, but Snake's stealth gauge will drop near an enemy even if you can't see him.
Stick to Shadows and Walls
Light sources will cast a shadow on Snake and expose him to the enemy. You can minimize your exposure to light sources by hiding in shadows and standing near walls and other obscuring objects. You won't cast a noticeable shadow if there is no light or you are next to the object that will obscure your shadow.
Play Dead in Cold Areas
Snake's breath can give away his location while on Shadow-Moses Island because of the cold weather. If Snake's breath is giving away his location, you can play dead to avoid detection.
Patience
While not glamorous, the key to stealth in MGS4 is patience. It helps to take your time to learn your environment so you can plot out your moves in advance. Additionally, you may have to wait several minutes for some enemies to move out of your way to give you a clear path.