1) ON LEADER & CIV : Get a warmonger leader. IMP/CHA/AGR/PRO are the traits you are looking for. Look for a secondary economic trait to help you out for your economy (ORG/FIN/PHI). SPI is also nice if you are good with civics, so you can abuse the Nationhood/Slavery armies.
(1a)DO NOT GET ROMANS/INCAS/PERSIANS
(1b)Look for a civ that is starting with Mining/The wheel/Hunting OR Agriculture. Beeline accoringly to AH/BW/Archery and plan for an early rush or defensive war.
2)ON MAP : Play a Terra (bit harder) or Pangaia map. This will help you know your enemies from the start.
(2a) : Get scouts out fast and use them to scout the whole continet ASAP. Know your enemies is the most important in warfare. Also, use scouts to fogbust barbs and also keep the fog away from cities you want to settle
3) ON MILITARY PRODUCTION : Have always some cities dedicated on building units. Only build Forge and happyness/health buildings when you see the according faces
(3a): Have an early production city cranking out only Atacking units and your UU if applicable(Axes/Maces/Horse Archers/etc)
(3b): By the time you hit Construction, have a second city building ONLY Siege units
(3c): By the time you reach Feudalism OR Machinery (whicever first), have a third city building only DEFENDING UNITS (Longbowmen or Crossbowmen if you have iron + Spears/Pikes)
(3d): Make sure EITHER city tht produces atackers/defenders is also a port to later produce your navy. The other will produce your Airforce
4) ON ECONOMY : Play your leader traits. If he's financial, Cottage up every non producing city. If Philosophical, use more specialists. You catch my drift..
5) ON WONDERS : Only build ANY wonder if you have the related resource. Exceptions are : Great Wall if Imperialistic, Stonehenge if Charismatic (or have a monument as UU-Egypt/Native american/Ethiopia) and Pyramids if Philosophical and plan on a specialist eco. Still, only build wonders that help you achieve your purpose.
(5a) Have only 1 city to wonderspam. No other city should ever try to build a wonder..
6) ON VICTORY Enable ALL victory conditions
(6a) You should only win though with Conquest OR Domination
7) ON ESPIONAGE : Always run at 10% espionage (unless defecit research at 100% to win a tech race).
(7a) Use the espinonage screen and adjust the way you spent your EPs. Rank 1 on all leaders. Add one more if they have a diffrent religion than you. Add one more if you share a border. Add one more if you plan to attack the target OR are in War with them allready. Add one more if you have close borders
(7b) Use spies to sabotage the military resources of your target at peace and Support City Revolts at war (either to skip bombardment of defenses or stop unit production)
8) ON DIPLOMACY : Your neighbour is your enemy.
(8a) You will attack your neighbours first. Find out who their enemies are and ally with them. Find out who their friends are and ruin their relations. (a trick here to help : use a spy to sabotage the resources they use to trade with their good friends. Use missionaries to change the religion of their friends as well)
(8b) You should always have 1~2 good friends and war allies. Make smart choices : the furthest they are, the more time you will be friends. Try to always give into their demands.
(8c) Whenever you can bribe a war, DO IT!
9) ON AGGRESIVE EXPANSION : Never keep a city you do not need.
(9a)Holy cities, Cities with a wonder, cities that can help you establish a better border are always good.
(9b) cities that do not conect with your heartland are not good. Either raise them to dust of if you plan to capitulate their leader, let them join back.
10) ON GARISSON : Use the minimum number of defenders in every city to keep it under your control. That is usually 1
(10a)You can keep more defenders if under HR
(10b)You can keep more defenders to avoid culture revolts/swaps
(10c)You can keep more defenders at borders of any civ that is not your vassal.
(10c+)Keep defenders that make sense. If Justinian is next door, build Pikemen/Phants to take down his Cataphracts. Dont build Maces to defend vs Knights and vice versa.
11)ON PROMOTIONS/STACK COMPOSITION : Your stack should have a ration of 1/1/1 on attackers/defenders/siege. Attackers would be either units of foot with CR promotion or anything that can get a withdrawal chance. defenders should be Shock axes/maces/xbows, formation spear/pikes. AND garrison units. Your siege should have a balance of CR/Collateral and bombarment units, with emphasis on the collateral ones.
(11a)Keep with one line of promotions. If you start a medic, get medic2 (and three if possible), March.. if you go combat, go all the way up untill 5. If you go Guerilla, go all the way up to 3.'
(11b)ALWAYS have some medic units in your stack(in case you loose one to unfortunate event). Medic 3 is overrated to spent a GG. Use a C1.Med1&2 or a woodsman 3 and then go for medic 1+2.
12)ON GREAT GENERALS : Settle all you can untill you can get level 3 units out of the gate of your heroic epic city.
(12a) If Imperialistic, attach more GGs to units with leadership promotions and have them FIGHT. You will get more GGs this way...
13) ON UNITS : If a unit is not highly promoted (that is : if you can produce a unit with more xp than the one you have), delete when it is past it's age and replace with a new one.
That would be pretty much it. GL!!!