The Duchy of Apulia is a decent starting place for many characters is 1066, with a fair chance of surviving until the end.
Above average starting ruler, Robert de Hauteville. Robert spawns as a brilliant strategist, and some decent traits. He
typically has roughly 18 in martial, and decent in all stats except diplomacy. He does not however, have any genetic bonuses, harmful or helpful (With dlcs he sometimes spawns with the strong trait). Robert also spawns in at 51 years old, but has no negative health traits and should live to his mid 60s unless assassination, illness, dying in battle, etc.
Easy access to early land. A holy war for Sicily on several divided Muslim states on the island of Sicily can get you quite a bit of land, and while declaring holy wars, your chancellor can be fabricating claims on the isolated Catholic counties such as Amalfi, Salerno, Capua, and Neapolis.
All of your children are still young, and you can educate them to become brilliant strategists. (side note: It is recommended to educate your first and third son: Bohemond and Guy, as your second son Roger has the hunchback trait, as well as lower stats overall) Your first son is not under your education, so immediately change him to your character.
Rich Neighbors: You are surrounded by merchant republics, which gain money quickly and will offer to give you that money in exchange for marrying women in your court, usually close family, but it can be distant family or even unrelated courtiers. Also, should you go to war with them for embargo or non territorial reasons, they will pay you a hefty sum should you win.
Succession Laws are easy to change in Apulia, as you are independent and can choose any you want. You have positive relations with your vassals, and any succession type is available, depending on your preference.
Powerful Neighbors: Both the HRE and the Byzantine Empire are right next to your door, but worse, the Byzantine Empire has de jure claims on your land! Also, though not as likely, the Muslims in Africa and Sicily may band together to stop you from taking Sicily, or to take your well-deserved land off of you.
Picture: Muslim African Counties that will band together to stop you. However, if they declare war on you, many Catholic kingdoms and duchies will ally with you to help you win.
Economic Disappointment: You start off with only about 70 gold, and your many personal levies needed to take Sicily will deplete that extremely quickly, and looting will not replenish your coffers fast enough. This can be combated by your merchant republic neighbors, who will offer between 1 and 600 gold to marry women in your court, sometimes not even members of your family.
Land: You have 3 sons, all unlanded and eager for fiefs. You also only have 2 counties, both of which only have 2 holdings, with a maximum of 3 holdings. You also have very few vassals, which means most of your army will be from your personal levy, and your personal finances.
Large Family: You have many brothers, sons, nephews, cousins, etc, In your family, which means several things. You are extremely unlikely to die because of a lack of heirs, as your family is massive. Most of your brothers, nephews, and nieces are educated with martial skills. Most of your brothers and nephews have either the brilliant strategist trait or the skilled tactician trait, and can pass these skills on to the next generation. However, these family members all have claims on your titles, so be careful with them. Should they rebel against you, their martial skill will make their armies even more lethal. Treat your family carefully, or it could come back to haunt you. Your wife is also young and may have a couple more children before Robert's death.
Picture: Your youngest brother Roger, already Count of Messina. He is also your best commander and he makes a loyal vassal. Be good to him and your other siblings, or they will rebel.
Culture: You spawn a Norman in Italian land. This is not a huge deal, but it will take a few years for the peasants to embrace Norman Culture and Italians to disagree with you.
Before you even unpause, you must do several things. First, change the guardian of your eldest son to yourself, and when Guy comes of age, make yourself his guardian. Second, change the guardians of children in your family to suitable people. Try to use military education, as you will need a lot of commanders in your starting years. Finally, make alliances with anyone you married off, family members, and the count of Capua. You will need allies in case the Muslims call in there own allies. Unpause, and declare a holy war on the Sicilian counties held by Muslims. The crossing between Messina and Reggio can repel armies larger than yours if they cross it, but it works both ways. Should they block it with equal to or slightly less troops than your own, use a vassal's navy to get your troops on Sicily. You must strike hard and fast, as the Count of Neapolis and several other counties will declare war on the Muslims in Sicily. Crush their armies, and siege their territory. You can use Robert de Hauteville in battle, but be careful, he is old and his son have a difficult start should he die. [Even worse, in one of my playthroughs, he was knocked incapable in battle]. Keep declaring war on the Muslims, until you drive them off the island. Give out land to your sons, nephews, and brothers. Give a bishopric to your second son Roger, this will disqualify him from succession and in his later years you might be able to declare him the anti-pope and make him the new pope as Bohemond (or another heir). Leave them alone at Malta, and turn your attention to the isolated Catholic counties. You should have kept your chancellor fabricating claims on them while you were at war with the Muslims. If not, wait for your finances to grow and set your chancellor on them now. Do not attack yet. and even worse by now your finances are slim at best, if not bankrupt. Keep on attacking when you can until you can take the isolated Italian states, The Muslims, and Malta. After setting your preferred Succession Law, create the title Kingdom of Sicily. After the war, start marrying off your family.
You might hit a block after making the Kingdom of Sicily. Your neighbors are too powerful for you to attack, you have to wait for vassal levies penalties to decrease, and the years crawl by. The next steps are up to you, but I strongly recommend gaining as many allies as you can and getting claims on the HRE-held Kingdom of Italy. If your lucky, the HRE will become a heretic state and the pope will call a crusade on them. Or you can declare war on them with as many allies as possible right after they fought in a war and hopefully lost. If they have a revolt, the Italian states may become independent. If so, jump on your chance, and when they win, take their new territory from them and add it to your own. Participating in Crusades can also greatly help you expand. Sooner or later though, the Byzantine Empire will declare war on you for the de jure holding of Lecce. Surprisingly, you can win, even if your heavily out-manned. The Byzantine Empire will send armies at you, but they will not bunch up into one massive army, instead separating into 3-5 armies. If you trained your family to be excellent commanders, use the crossing from Lecce, and the Byzantine Empire splits up their armies, you can repulse them. You may need mercenaries to help secure Lecce, and if the Byzantine Empire combines their armies, you can still win. Just use attrition and bait them to follow you across the map until you can get Lecce again. Lecce also has many mountains, so no matter what direction you attack it from the defenders will always have an advantage.
Picture: Sultan of Africa declares a holy war on Apulia. Catholic Kingdoms and Dukes oftentimes offer to help against these threats.
Hope you enjoyed, and stay tuned for any other articles I may write! -Exotic Lemon