A friend of mine used to be a MODO ringer in high school, took a break from the game in college, but now is in the real world and wants to play more Magic with his copious spare time. He's been asking me what he should know before jumping into the shark-infested waters of Pro Tour Qualifiers.
I told him to read an article Zaiem wrote this for Channel Fireball, and I'm sure he's written it for other sites too:
Tournament Mistakes.
The best way to get used to playing in PTQ's is... to play in PTQ's, so I was a little worried about overloading him with information. I think the right way to go about this is to go through my routine. I'm a little bit more of a nit than others, and all I have to show for it is a Day 2 of a Grand Prix, but if you're still curious...
Deck registration - Don't misregister your deck. Just don't do it. Be careful, count the cards you write down, count the cards in your deck/pool. That's all there is to it, but it's still bound to happen if you're careless. I misregistered my second draft of Grand Prix: Boston, and it probably cost me $200.
Pairings - Make sure you have the table number right, and also the guy's name. That way you can be sure you're in the right place and playing the right person when your opponent sits down. Sitting at the wrong table is Game Loss worthy.
Tardiness - If your opponent is not in his seat when the round starts, call a judge. Depending on the head judge, your opponent either has three minutes to show up or else gets game loss or he gets one right off the bat, but you should call a judge anyway so he knows to look for you when 3 minutes is up. Ten minutes is a match loss. You should write down the time from your cell so you know when to call the judge.
Shuffling and presenting your deck - I always pile shuffle my deck to make sure I have everything in my deck. It unclumps your deck and keeps you from giving up game losses for presenting an illegal deck. In Constructed, I also look through my sideboard to make sure it's correct before officially presenting, in case you get deck checked.
You have three minutes before each game to shuffle your deck. With sideboarding, it's a little wishy washy, but definitely after 3 minutes you should call a judge and let him know. He'll probably present right away when your hand goes up.
You should always shuffle your opponents deck. I start by piling his deck, and if he's short a card, my hand goes up for a judge because he's getting a game loss. I'd also shuffle his deck pretty well before hand.
Life totals - I'm more of a nit than others when it comes to this. I write down both life totals with every life change (so I always see the current life totals right next to each other), and make a note of where the life change came from, usually with just the initials of the relevant card. This way, if there's a discrepancy in life, then you have an accurate representation of the game. Of course, you shouldn't try to cheat like this, but you're basically protecting yourself from someone who tries to work you on life totals.
Hands - God almighty, make sure your opponent keeps his hands above the table at all times. If you see them dip, make him keep them up. A lot of players don't mean to do it, but this is why it's a way to cheat.
Being clear about the game state - Your opponent must always answer what phase the game is in, what cards are in what zone, must let you search his graveyard and count the cards in his hand or library, and relevant actions that have taken place (i.e. playing a land, casting a spell). There are some questions that your opponent is actually not obligated to answer, like the P/T of a creature, the number of cards in hand, but he must let you be able to figure it out. Most players, however, don't know that they aren't obligated to answer such questions and will do it anyway, so this is actually moot. I'm planning an article about why players aren't taking advantage of the Derived Information and communication guidelines.
Slow play - You can at any time call a judge and ask him to watch your game for slow play. You can also urge your opponent on if he's tanking for an unreasonable amount of time. Calling for a judge with two minutes to go in the round is pretty moot, so you can be vigilant about it. I usually keep an eye on the clock and see if we're making good time to finish three games: 15 minutes per game should be the pace.
A very good player has said that when he's tanking toward the end of the game, he will actually call a judge to keep himself honest with slow play. And by the way, pretending your thinking to take advantage of the time limit is Stalling and is considered cheating, but making actions to prolong the game and playing for a 1-0 win or 1-1 draw is fine.
Illegal game state and missed triggers - If you and your opponent fail to note a mandatory trigger, you will both get warnings for failure to maintain the game state. If you note the trigger that your opponent missed before it's too late (like forgetting to draw a card), you can call a judge and he will get a warning.
For upkeep triggers you don't want to forget, you can put a die or a pen on top of your deck. For upkeep costs, you can put tapped lands under the relevant card so you don't accidentally untap them.
Judge calls - You're entitled to appeal any ruling you get from a floor judge to the head judge. Do this if you think you got an incorrect ruling.
If you're receiving a lengthy ruling from a judge, you should write down the time the judge comes over, and then ask the judge for extra time. He may or may not grant it, but you can always appeal, and you know how long the judge call took because you wrote down the time.
Drawing extra cards - Drawing a card/extra card when you're not supposed to is a game loss. All I can say is don't do it.
Deals - You are not allowed to prize split *in exchange* for a draw or a scoop. You can prize split without a draw or scoop being a contingency. You can ask for a scoop or and ID without any agreement. If you get caught doing one of these things you're not allowed to do, you're getting Disqualified. If you want to be a jerk (i.e. the win will get you or a buddy into Top 8), you should call a judge when your opponent or someone you see does one of these illegal things before submitting their match slip. If you don't want to be a jerk, though, you can very firmly say "I cannot accept that."
Drawing into the Top 8 - If you've never done the math before, consult with someone who has done it before the final round to see if you should draw in or offer a draw to your opponent.
That's all I can think of. Feel free to chime in some more.