"I'm excited to go to Chelsea now," he said.
"It hasn't really sunk in yet. When I go there for the first time as a player, it will be special. I'm really looking forward to it.
"I'm not sure how many tickets I can get for friends and family.
"I probably won't be able to get many but we'll see."
Palace have kept four clean sheets in the past five games and go to Chelsea in confident mood.
There's no hiding the fact Jose Mourinho's men will pose a different test, but Williams says he's always believed in what his defensive team-mates can do.
He said: "I think our defence has always been good. Ian Holloway had them in shape previously and I think it's just carried on. There are no risks.
"We defend really well, and they're not exactly hoofed either – they're accurate, diagonal balls.
"That's really helped us to break on teams, and we didn't really take our chances at the start of the season.
"It was a fine line between getting a point and not getting a point against Tottenham on the opening day.
"It just wasn't going our way, but recently we've had our luck and it's been a great feeling."
