The year is 1081

>The year is 1081
>Turks have conquered almost all Anatolia
>Somehow you become emperor instead of Alexios Komnenos

What would you do to save the empire and then expand it in the long run?

Invade Poland.

ask the pope for help. after the disaster of manzikert 10 years earlier I have not the military power to wage war on the turks, I need outside help.

convert to Islam

Empty the treasury and move to Italy or something

Sail to Africa to suck on big black cocks and watch my wife get pounded by the superior black specimens for the rest of my life.

Require the use of an asterisk in all references to T*rks, that'll show em

WE SHOULD DIG A MOAT!

Basically do everything he did up until 1097 or so.

Not turn back from the march to Antioch due to the cowardly retardation of Stephen of Blois. This will have led to the Byzantines reclaiming Antioch and also helping maintain (reasonably) good relations with the Crusaders. A Byzantium that holds Antioch in this period will much more effectively project power into Syria and the Crusader States than it did historically, and would probably make it much easier to evict the Turks from Anatolia, which the empire was doing with great success until the sudden death of John II.
Also stop the endemic short-termism that haunted the Komnenos dynasty. Start trying to rebuild a standing professional army like under the Macedonians, rather than just relying on mercenaries all the time. Also make sure John succeeds me and try to discreetly get rid of that fucking idiot Manuel, send him to a monastery or something.

Beg Frankish barbarians for help like a little bitch.