Check your official papers and be careful not to forget anything from them after installing the entry stamp.
Spend a sufficient amount of money for approximately one day's expenses in local currency at the cashier located at the airport, as you will find yourself having to pay your expenses in local currency only.
Book your car from the airport if you want to rent a car during your stay in Turkey, as the offers available at the airport are considered good and safer, and early booking a car may save you some money from its rent.
Or if you know the destination you want to move to, and you are able to get around by public transport, then at the main gate of the airport you will find the airport bus station, which is distributed to a group of points in the city.
Get a phone line from the contact company located at the airport, usually these lines are included in numerous service packages and are sufficient for you during your flight.