Any silly suggestion of amnesty for "the good ones" has already been tried and proven to be a HUGE failure...amnesty simply spawns many more-- and THEIR myriad spawn!
As for how to get them to return at THEIR own cost, simple TRUE enforcement of EXISTING laws would effect that goal. No jobs and no freebies? Vamanos muchachos al Mexico! President Eisenhower got quite a few to return at moderate cost with his "Operation Wet-back." We need only a similar will in the W.H. to enforce the law-- which every POTUS takes an oath to do (even the Obamanator).
"Eisenhower had a sense of urgency about ILLEGAL immigration upon taking office. In a letter to Sen. J. William Fulbright, Eisenhower quoted a report in The New York Times that said, "The rise in ILLEGAL border-crossing by Mexican "wetbacks" (rooted from the watery route taken by the Mexican immigrants across the Rio Grande) to a current rate of more than 1,000,000 cases a year has been accompanied by a curious relaxation in ethical standards extending all the way from the farmer-exploiters of this contraband labor to the highest levels of the Federal Government."