During gameplay, in the text menu (on either all or team) type for your character to hum/whitsle/sing a part the Metal Gear Online melody.
Have MGS4 savegame on your stick at the end of the game to unlock all music tracks.
Break The Cycle Of Auto-Aim
Equipping your cardboard box and staying still will keep your character safe from being locked on (but not from being shot manually).
Stop Drop And Roll
If your character is set on fire, you can extinguish the flames by quickly equipping the cardboard box.
A lot of you probably know this but I'm just putting this out there since I camp the roofs in Urban Ultimatum and similar stages often. When your character is on a ladder, you can throw a grenades.
Online Stealth Tips
When playing as Snake in the online sneaking mode, you should avoid lit areas so your shadow will not be as apparent. Also, in stages where characters emit frosty breath, have Snake play dead while prone to make Snake's breath disappear.
Trying to find a friend on Metal Gear Online but can't? That's because a player needs to log into their MGO account (and onto a server) before you to find them. Additionally, you "add" their MGO character name to your Friends List (for Metal Gear Online only), not any other Playstation Network game.
Box Hide Trick
If you already know that equipping the box makes you immune to the porno magazine's effect, then you should try doing that while climbing a ladder. The game won't register the magazine since your character immediately goes into the box once he's off the ladder.
The cardboard box may restrict your view, but it also keeps you safe from seeing magazines. If you think that someone has placed one behind the corner, equip the cardboard box to avoid it.
Eagle - Large percents of headshots.
Snake - Perfers sneaking missions.
Turtle - Use the Cardboard box a lot.
Bear - Have a large amount of CQC attacks given.
Pigeon - Perfers non lethal attacks.
Rat - Falls for a lot of traps.
Sloth - Gets shot in the head a lot.
Flying Squirrel - Have a high percentage of rolling.
Jaws - Large Amount of Knife Kills.
Kerotan - Prefers Capture rules.
Night Owl - Use the ENVG a lot.
Bee - Uses lots of scans.
Crocodile - Very good kill death ratio.