Come down on any company hiring illegals aliens immdiately and dry up the draw.
Begin rounding up, arresting and incarcerating for a short period in work camps near the border, any illegals we can find, then expel them. If we seriously did these two things, we wouldn't need to worry about catching them all, most would leave.
After executing the above program for 90 days, offer any remaining illegals the following:
1) If you voluntarily report at a border station or any INS office, you will be immediately deported, but, after we take a DNA sample, if you pass a background check while we do so, we will consider your immigration requst favorably if you get in line with everyone else and apply through the standard methods.There's both the positive and the negative the incentive.
2) If you fail to report voluntarily and we have to catch you, or if you enter illegally again, then we will use your DNA to enusre that you are NEVER considered for immigration to the United States, then you will be incarcerated for 90 days abd expelled. If you are ever caught again, you will spend 20 years incarcerated, on work gangs before being expelled.
If they all go down south and build the fence for us we can let them apply to get back in when the project is over.