Doing it the right way staves off the possibility of bad luck (I don't remember where I found this, so sorry if I don't give the original Author Credit)
Before you hold the denaming ceremony, you must remove all physical traces of the boat’s old name. Take the logbook ashore, along with any other charts, books, or papers that bear the old name. Be ruthless: sand away the old name from the lifebuoys, transom, topsides, dinghy, and oars; painting over is not good enough. We’re dealing with gods here, you understand, not mere mortals. If the old name is carved or etched, try to remove it. At the very minimum, fill it with putty and paint over it. And don’t place the new name anywhere on the boat before the denaming ceremony is completed—that’s just tempting fate.You can read the ceremony with flair on the foredeck before a gathering of distinguished guests or, if you find this whole business embarrassing and go along with it only because you’re scared of what might happen if you don’t, you can skulk down below and mumble it in solitude. But the words must be spoken.
Now you are free to christen your boat with a new name. It doesn’t pay to be too quick, though. Most of us like to wait at least 24 hours to give any lingering demons time to pack their duffel bags and clear out.