Neil Harris hailed Cardiff's "huge achievement" of making the Sky Bet Championship play-offs and hopes momentum will carry his team forward after sending Hull down.
Junior Hoilett, Sean Morrison and Danny Ward were on target as Cardiff's comfortable 3-0 win saw them secure fifth place and drop Hull into the third tier of English football for the first time in 15 years.
"It's a huge achievement," said Cardiff boss Harris, who succeeded Neil Warnock in November when Cardiff were 14th in the table.
"Every bit of praise for the players and the staff has been earned.
"I came in as not a huge name and I had to prove myself, every week.
"The play-off (semi-finals) are about four halves of football and you need momentum."
Cardiff are the form team in the play-offs having finished with wins over Derby, Middlesbrough and Hull.
The Bluebirds will meet Fulham, the first leg in the Welsh capital on Monday, while bitter rivals Swansea will play Brentford.
"The message is clear," Harris said. "We get into the play-offs when everyone else is on holiday and that's to win. No other reason.
"There is a bit of pressure on us, bit there is huge pressure on Fulham. We will go and enjoy it.
"I have been through six, four as a player and two as manager and I love it. It's the best way to get promoted."
Nottingham Forest, fifth at kick-off, dropped out of the top-six after losing 4-1 at home to Stoke.
And Harris could not resist taking a dig at Forest, who recalled winger Albert Adomah from a loan spell at Cardiff at the end of June.
"Sabri Lamouchi (Forest manager) was manager of the year in the Championship four weeks ago and they finished seventh," Harris said.
"They stopped us taking Albert Adomah to take an advantage over us. It's a crazy league."
Hull will be playing in League One for the first time since 2005 after a miserable second half to the season.
The January departures of star players Jarrod Bowen and Kamil Grosicki prompted an incredible collapse which saw the Tigers win only once since New Year's Day and lose 16 times in 21 games.
"It's been disappointing for a few months now," manager Grant McCann said. "It's really frustrating but one thing we have now is a chance to regroup and bounce back.
"It's going to be difficult because League One is a tough league. Two to three weeks of hard work to rebuild start now."
McCann says he hopes to be in charge of Hull next season and is the best man for the job.
"I understand the fans' frustration and we haven't been good enough, but I have a burning desire to rebuild and go again next year," he said.
"I feel I know League One inside out and I'm the best man.
"People will look at us being relegated but bigger clubs than Hull have been in League One.
"I don't think it's anyone's fault. We haven't done what was asked of us since January."