One of the biggest things you should do is build lists you enjoy and have fun with. You probably be trounced into the ground the first few events you go to, but playing fun lists and things you enjoy will make the experience that much better. You don't need to win to have fun. You should just have fun playing and you get to meet some new people who share your hobby. That being said I'm sure your planing on going to tournament and rocking your list to the top spot. Here are a few things to do.
The first thing I do for a tournament is to get all of the rules. If you are playing Steamroller, download that packet. Found here....
Make sure you’ve read it and understand what it is saying. Compare what your event has listed to what is in the packet.
•A default Steamroller event is 1 list minimum, 2 lists optional.
•You have to bring at least 1 list, but you don’t have to bring a 2nd.
•Be aware of character restrictions. You can’t take the same character model in both lists, some events prohibit taking the same character of any version between both lists.These are rare but they do crop up.
•Be aware how many times you have to play your lists. Divide and Conquer and X Lists Required will change how many times you need to play each list. X Lists Required means each list once, Divide and Conquer means you have to play each list as close to even as you can. This will force different list builds.
Check for a painting requirement. Very few events will require it, but some offer painted prizes/raffles for having lists painted. Find out what the TO plans to do for this. Does it include basing? Do both lists need to be painted? Will players vote? Will the TO decide? Is it random?
After figuring out the event, it is time to list build. Here is a list of things to consider while building your lists.i have lost many a game because of these
•Can your list handle multiple high ARM models?
•Can your list handle multiple high DEF models?
•Can your list handle Purification/Hex Blast/Lamentation?
•Can your list handle Stealth?
•Can your list handle Immunities (Fire/Corrosion/Lightning) and general attack immunities?
•Can your list contest a zone/flag/objective?
•Can your lost handle rough terrain (either physical terrain or Rifts/Inhospitable Ground)?
•Can your list handle ranged superiority? AOE spam?
Then there is the matchup dependent considerations. My analogy is a Rock , Paper ,Scissors approach to list building.
Can you handle the top Cryx casters eAsphyxious, eDeneghra, or eSkarre?
Can you handle Menoths top two, Kreoss, and Harbinger?
Can you handle some Cygnar casters ,Haley,eHaley, and eCaine?
Can you handle some Circle shenanigans, Kromac,eMorvahna, and eKreuger?
Can you handle LOE tricks, Saeryn? Both Vayls,e Lylyth?
Can you handle the missile that is Molik Karn? how about e Makedas, or Zaal?
You can’t answer all of those questions in two lists. Its imposable. You do need to know which of your lists have a rock to your scissors . When building your list, figure out what it is good at, and then decide to make your second to shore up any weaknesses in the first. Be careful not to duplicate the same rock, between both lists, as this will lead to a "Paper" matchup that you’ll have a very hard time beating.
Now lets look at the scenarios ,you need to make sure to know which scenarios are easy to win. By knowing these, you’ll run into less issues of not being able to play a game due to your opponent winning scenario by turn 3. Also be aware of which scenarios have Killbox.Dont forget killbox isn't a instant loss ,it gives up 2 control points. Which in 2013 first to 5 Control Points wins.
With your lists in hand, it is time to pack .
Here are the things I bring.
Models for both lists, including models that get created in the game (extra Thralls, extra warjacks, etc).
Tokens for effects/abilities/focus/fury.
Enough dice (preferably two different colors, 1 of off color, 5 of normal)
Pen/Pencil (for marking your tournament sheet)
Cards for both lists (War Room and tablet if that)
Spray/AOE/Rings/Acrylic templates
Measuring tape
Laser
Carrying tray
I personally think you should mark your front arcs on models. During the event, it will really cut down on free strike issues with the marks.
This isn't comprehensive, but it does give you a good jumping point to start off from.
Have fun !