Institute a legal and humane means of population control and the closure of all point of entry into the United States for decades to come for national security reasons.
Do not deport. Simply fine anyone who employs an illegal alien or non US citizen $10,000 a day until the employee is removed from US soil and no benefits of any kind for any reason to these individuals.
In combination with this make it law that all H1B visa employers are 100% responsible for their employees both financially and criminally or for any and all actions and cost that may come from their employees misconduct.