"I have found a couple of things to be helpful.
1. If you are playing a catholic nation, take Navarre (it starts as rebels) by bribing the army there right away. This allows you to have spanish jinnettes right away. This is the only good light horse available to catholic nations and can be built easily. They give you a great advantage while other nations are still based on urban militia. Navarre is also a 'crossroads' province that allows you to take one of the other provinces and seal off Europe from the Almohads due to the mountainous terrain of that area. With some good bowmen, jinnies, some spear and highlanders I have held off superior armies of up to 7 times more men. 2. If playing Byzantium but the armies in Khazar. They are full of steppe cavalry and horse archers and are cheap. Abandon Khazar and make Georgia your northern border unless you plan on winning by about 1210...As Byzantium I have held Greece/Bulgaria as my northwest border and then taken all the way to Egypt (destroying the Turks and Egyptians) making that my southern border with the cavalry from Khazar and only trebizond archers and Byz infantry. Use Byz infantry in mass stacks and you can rule the map before the more advanced catholic units appear. Use them like the Roman legions they are. 3. When setting trade routes to the profitable Italian/Sicillian/Egyptian provinces have at least one 4 stack fleet wherever there are hives of other ships, especially Italians, Byz and Sicillians in the high profit areas. After about 5-10 years in their waters (or right away for Byz) they will attack you en masse. 4. Find an easy to access rebel province you can launch a crusade to and return from. Do this at the beginning and keep on sending crusades there to take and then return. In 4-5 crusades you will have a full stack of heavy crusade knights and footmen. 5. If you are on a roll, but can't take the map by 1210 or so... herd the other factions into between you and the steppe provinces. 6. If you can, take Kiev right away and fortify it. Steppe cavalry are the best. The can sweep right in front of enemy lines (at a right angle) chasing archers in front of them with spear running to keep up. 7. As a catholic nation use turcopoles as quick as you can. They are deadly for keeping heavy cavalry distracted or causing mass attrition on rear and flank foot. -That's it, hope it helps!" - Puhallo

"1.when you are playing the english, you better counquer first scotland and build a highlanders troups, they are cheap but powerful shock troops against france or any other country you wish to invade. 2. Never attack a nation that have allies the same as yours, it will be a disaster if they cut of the alliance that you have to them, if they cut it off they will soon invade you. 3. Always use princesses to be married to other countries you wish to be allied or to the generals you wish her to be married, if you ignore your princess it will be the end of your blood line and your kingdom. 4. It is best to target and counqer the province with so much resources and trade goods, it will make your country to become wealthy, The best province I prefer to earn more money is scandinavia. " - General Maximus Decimus Perillius