"This is our second international competition together so we didn't expect anything.
"We wanted to come here and put in a good performance and if we got a medal it was a bonus. To get a gold medal is amazing."
Daley admitted this week the synchro was his best shot at a medal at next year's Olympics despite the 16 year-old being world champion in the individual platform.
He admitted a victory at such an early stage of his partnership with the 30-year-old Waterfield would be a significant boost to their confidence, especially after claiming a rare win over the Chinese who had won all but one of the 17 gold medals on offer at World Series this year.
"The Chinese don't lose, especially with those two young Chinese divers who when you come up against them most people say silver is gold," Daley said.
"We just went out there and did our best; if you put the Chinese under pressure they don't like it.
"It normally takes years to get the right timing on the board and we are very lucky to naturally have that timing. We just need to now work harder and harder because we have lots more to get out of the list.
"Like Pete said we missed our first two dives, so we can do a lot better.
"But, honestly it does feel amazing especially to do it in front of a home crowd."
Daley's victory was made more emotional after his ill father was able to make the trip up to Sheffield to see his son claim gold.
Doctors last month diagnosed Robert Daley with a second brain tumour which has left him in poor health.
The 40 year-old had only previously missed Daley's gold medal-winning performance at the Commonwealth Games last year and made a late journey to see his son's latest triumph.
"It was good to see him earlier because he wasn't sure if he was going to be here," Daley added.
"He got a bit upset actually because it gave me that extra bit of motivation and drive to see him there in the audience.
"He has a t-shirt that says 'Give me oil in my lamp, keep me burning.'
"Apparently I am the oil in his lamp and I keep him burning.
"He's a little bit teary, he didn't think he was going to get up here because things obviously haven't been going well -it's been a tough time.
"I was glad he was up here to see me and Pete do as well as we have done today."
In the women's 3m synchro Rebecca Gallantree and 14-year-old partner Alicia Blagg proved they are able to compete with the best after finishing fifth.
While they never truly threatened the medals they finished less than nine points behind third place, with China's He Zi and Wu Minxia maintaining their perfect record at this year's World Series to win gold.
Earlier, junior world champion Jack Laugher underlined his growing reputation by posting an international personal best in the 3m springboard.
Laugher overcame cramp in his right leg mid-way through the competition to score 436.90 and continue his improvement in his first year in senior ranks.
The competition was eventually won by China's Qin Kai who again beat his countryman and Olympic and world champion Chong He while Hu Yadan won the women's 10m platform in the night's final event.
