1. Never answer the door.
2. Never leave home.
3. Conversely, never go home.
4. Don't enter or exit your workplace.
5. Stop hanging out where you did before you got sued.
6. Pack up and move in the middle of the night.
7. After a few months, repeat steps.
Ok, seriously now. If you don't answer the door when you see the process server out there, your plaintiff's attorney will probably just pay her more to show up at your job or sit outside your house until you come out or go in. And they'll add the cost to whatever they're suing you for.
The longer it takes, the more you might have to pay the person you were avoiding for so long, because she will eventually catch you off guard.
Finally, you're still considered served even if...
...you didn't touch the papers,
...you threw the papers on the ground and walked away,
...you don't personally know the process server,
...the process server didn't show you a badge or ID,
...you told the process server she's not allowed to serve you,
...you spoke to the process server from behind a door or window,
...you told the process server you disagree with the plaintiff, so there's no case,
...you chased after the process server and put the papers on her car windshield,
...the process server gave the papers to somebody you live or work with.