Although he's never been in the house himself yet (hint), Jamie reckons he knows how the celebs should behave if they want to come out as champions.
Or at least leave not looking like a total knob, like a fair few manage to do.
"The one bit of advice I would give would be you can't walk in there as a celebrity," he says, before complaining: "The amount of the celebs we have that speak to me before entering saying: 'I'm going to stir it up', then get there and they won't say boo to a goose'."
And Jamie's perfect housemate?
He explains: "My dream celebrity housemate has got to be Joan Rivers. I think if anyone has a wish list, they usually have Joan Rivers right at the top of it. We just need to get her in before she dies."
If you prefer to watch rather than read, then you're in luck.
Here's Jamie saying all of the above a lot more in video form...