Firstly, this guide is not for people who play this game exclusively to amuse themselves. This game offers discipline, self-introspection, and the development of patience and perseverance. You can apply things you learn from this game in many other parts of your life.
THESE ARE ONLY SUGGESTIONS. Please don't post that 'this isn't how I get my head-space'. I realize just by asking people not to post that I'm pretty much demanding that ten or twelve idiots post exactly that.
These WILL work for SOMEONE.
Starcraft 2 is a very 'pure' game. Each element of it can be exploited to offer genuine advantage on the battlefield but none moreso than your own mind-set. If you've spent any time with Day 9's videos you realize early on that attitude is a huge part of it but how do you get attitude? This is a list of simple ways before you go into a game of working out your own attitude. They may seem a little arcane but I promise, they help.
1.Visualize your end army composition. This is the army you want to build, constructed regardless of the opponents actions. Close your eyes and formulate the model of each unit in your head. If you are Protoss, take the Zealot first. See how many you will want in your composition and why they will be there. Are they going to be tanking damage or dealing it? If they are dealing it, what is keeping them alive and allowing them to close with the opponent (obviously Charge and Sentry Guardian shield).
2.Think of the unit that scares you the most. For me this has and probably always will be Banshees. Yeah, they scare the crap out of me. Once they're on the field, I am just having a bad day. I know the list of counters and methods of dealing with them. There are plenty and Protoss will soon have more due to the Phoenix and Observer buffs.
That isn't the point. Visualize the unit. See it in your mind's eye. Now see a huge army of them. A terrifying army. Now make that army crumble. Shatter that army and break it's back with a mass of your own units. If you do this mentally you can actually find yourself looking forward to the actual encounter with the unit or composition that frightens you.
3.Become a sado-masochist. Take the death of each of your units with a smile and the death of each of his with a giggling grin. Imagine their deaths and enjoy the spectacle. If you are a nasty bastard killer, those deaths mean nothing. Win or lose, know your opponent would fear you if he could see into your head at this moment.
4.Be the cold center of the world. Be empty of emotion. Before each game, take your feelings about what you are doing, who you are playing, and whether or not you are going to win and put them outside of yourself. You can do this by imagining a spinning blue ball full of all of your feelings and then mentally placing it outside of your head. It's a simple piece of self hypnosis but it works surprisingly well.
5.Meditate on your plan. Take thirty seconds before the game and close your eyes. Are you cannon rushing this game? Are you going to do early pressure or early defense? Make each decision before the game has begun and before the loading screen appears. If you have the game in your mind and your opponent doesn't you will own the playing field.
6.Imagine the game as a long term war. If you lose this battle that doesn't mean you've lost the war. The war is ongoing and your units are only meaningful in the way they contribute to that war, not in how they contribute to this battle. If they all die then they died for the cause. Think of the 'Surrender' button in the menu as a 'Retreat' button. You live on to fight another day. You can come back to this battlefield and win the day in the future.
7.Think of each of your units as hugely over-powered. Look at them as power-houses of monstrous strength. Even should they die it wasn't because they were weak. The only weakness is inside you and those weaknesses inside the human being are the ones that can be defeated most easily. You might make a gun fire more bullets but it won't matter if the man behind the gun hasn't the will to fire those bullets. Imagine yourself moving mountains with your army. If you have the will, your army will have the will.
This is a list of traps people fall into that they MUST be aware of. If you are falling into any of these, you should know that these will steal strength from your army as much as they steal it from your mind-set.
Trap 1.The Game Is Imbalanced-Everyone is guilty of this at one time or another. Awww, man, those Roaches have such shitty range. My buildings fell SO fast to that Marauder drop. God, those Stalkers just don't do enough damage. Man, Archons suck so bad. If you find yourself thinking this, see #7 of the above list. If you believe your gun is smaller than the enemies and your will is weaker, you will not prevail.
Trap 2.All the other players seem so much better than I am.-They aren't better. More knowledgable perhaps, for a time. They know the decisions more intimately. They are human beings. Two arms, two legs, a nose, eyes.
Trap 3.I hate losing so much!- Get on the ladder today and lose 10 games. Do it on purpose. Throw endless waves of units away. Let the enemy straight into your base. Don't build defenses. Let them stomp you and have the win. Then, when they win, go and tell them they're the best player you've ever fought. If they make fun of you or call you names all the better. Tell them they're right. LOSE HARD. If they say 'You suck, faggot' say 'I sucked ten dicks today. Thank you sir, may I have another?'.
Crush Your Ego. You don't deserve to win until you can win without defining yourself based on how much you win.
Trap 4.I must practice like Huk or I'll never be as good as he is!- No, you are not trying to be as good as Huk. Sorry I keep using him as my example but I've been watching his replays a lot. Go out and play a pick-up game of basket-ball. You aren't trying to be Michael Jordan or Kobe Bryant. This game is not about being God. Just because you can climb to compete in the same leagues as those players with less luck than is involved in being picked up by an NBA basketball team you should not make this your goal. If this is your goal, be prepared to sacrifice large parts of the rest of life to do it.
Don't try to be someone. Imagine yourself being them if you must, but be YOU.
Trap 5.I shouldn't steal someone else's play style. I should be able to make my own!- Yes, yes you should steal their play style. If you can make it work for you then by all means, rip it off right at the root. This is another ego thing. You are not Picasso. You do not need to be hugely creative. People name tactics after players in chess and fencing for a reason. They acknowledge the truly creative ones but they also make use of those tactics. Lalush style, Jinro style, oGsMC style...Use what you see from them.
Trap 6.My replays will just show me losing. -Your replays will show you how to win the next game. If you are so embarassed to watch yourself lose, see the solution to Trap 3. Then watch your damn replays.
Okay, I'm wrapping this up. I realize it's long but I hope it helps. Attitude is the core of life just as it is the core of this game.