DULLES, Va. — The escape plan was carefully choreographed. On Friday, after a day of work, Representative Paul D. Ryan pretended to turn in for the night, walking through the front door of his home in Janesville, Wis.

He did not stay for long.

To elude reporters camped outside, he slipped out the back door with a suitcase and walked through the dense woods that surround his property. He exited on a nearby street, where an aide in a waiting car drove him to the airport.

His destination, the Republican ticket.

For the past 10 days, the Romney campaign took extraordinary measures to keep Mr. Ryan’s whereabouts and movements a mystery. In the process, the campaign pulled off a rare feat in the era of the Twitter news cycle: Mr. Romney unveiled his vice-presidential pick on his own schedule, keeping his running mate’s identity secret until a few hours before a rally in Norfolk, Va., on Saturday morning.

It required painstakingly planned skulduggery, which the campaign outlined in detail, late on Saturday afternoon.