(1) Make the process open, transparent, and timely, with hearings, drafts on the Internet, and no last-minute bills that no one has read;
(2) Earn people's trust, don't demand it, and treat enforcement like it matters;
(3) Respect people who follow the law, and make legal immigration easier, cheaper, and simpler, rather than the Kafkaesque nightmare it is now;
(4) Don't feel you have to be "comprehensive" -- address the problems you can deal with first. The trust needed to deal with other problems will come later, after you've shown some success and some good faith.