1. Constantly check your own and your opponent's graveyard to know what cards have been used.
A simple move that goes a long way in your games, constantly checking the graveyards allow you to remind yourself what spell has your opponent played and how many copies of a card is left in your deck. If your opponent has exhausted all 4 copies of his Day of Judgement, you have no more worries of pouring all your creatures to the battlefield!
2. Take lots of notes! Whenever your opponent searches his library for a card, or after you've Duress them, take note of the cards in your opponent's hand.
Knowing what cards your opponent has in hand allows you to plan out your moves careful to avoid falling behind tempo and cards. If your opponent has revealed a Consume the Meek via your Goblin Guide, take note of it so you won't over commit and walk straight into it!
3. Take your time to consider your options and outs before rushing into a decision, it's too late to pull back once you've made the wrong play.
Think carefully and consider your options before making a play too quickly. You might be excited when you pull a Lightning Bolt of the top when your opponent is at 3 life, but don't be too hasty and slam it down when your opponent has tons of open mana! You might walk into a counter magic or damage prevention that then cause you the game. Consider your options, and then play accordingly.
4. Prepare notes for yourself to read during sideboard time to remind yourself your game plan against a specific deck.
With the new M11 rules, it is now legal to bring notes and refer to them between rounds and games in a tournament. Write up notes regarding your game plan and sideboard against different decks, and then refer to them during sideboard time to reaffirm your plan.
5. Learn to mulligan aggressively if your deck relies on specific cards to work.
A lot of hands seems playable and decent, but if your deck needs a specific card to operate or a specific hate card that single handedly win you games against your opponent's deck, throw them away till you find the card. If you're opponent is playing a deck base relying on graveyard, you can afford to mulligan down to 5 to find that sideboard Leyline of the Void and still win the game.
Author Resource:
The are just a few of the many hints and tips which are available in the MTG Guide - Play Magic like the Pro's. For more information on the guide visit : Mtg Fanatics - Play Magic like the Pro's