Some occupations that are necessary for a community to function have either been largely taken over by illegal immigrants in certain regions or cater to illegal immigrants. Construction is an example of the former while many in the banking industry have decided to cater to illegal immigrants by offering loans, check cashing, wire transfers, etc. As noted in the last post public hospitals are forced to provide non-essential medical care.
Encouraging citizens of a community to focus careers on these industries will both provide an alternative to illegal immigrant labor and destroy the infrastructure that allows/encourages them to stay. Construction jobs are tricky, as many of them have been gutted by low wage illegals and the owners willing to exploit them. Those companies hiring legal workers will be at a disadvantage, for a time. However, a community willing to hire only Americans from the community will a) find work done properly, b) be supporting their and local community and their country's economy, and c) reducing crime and dependence on social services (and therefore taxes). Illegal companies could eventually be driven from the scene.
Local banks very often offer higher returns on savings and CD accounts, and might offer better loan rates (the reason being, apparently, that they spend less on advertising than the large banks). Local banks can be set up only for community residents and U.S. citizens. (Ever been to a Bank of America in a border state? Real fun to stand in a long line with the other citizen customers while the illegals get a line ONLY FOR THEM. Yes, really. And thankfully I'm no longer with them.)
The medical professions should also be targeted. If members of a community encouraged current medical professionals to leave public hospitals, and if the children of the community were encouraged to become nurses and doctors, hopefully the local public hospital system would only be able to provide emergency services and not the current benefits provided to illegals. Many regions have faced the closure of public hospitals because of the burden being imposed by illegals, and setting up an alternative private system will spare citizens while inconveniencing those illegally here, as they won't be able to access it.
Taking back these professions will reduce how much you pay in taxes, will make your stay at the hospital much more pleasant (and potentially life saving), and will support the local economy instead of Mexico's.