PORT ST. LUCIE — This time last year, catcher Travis d’Arnaud boldly told The Post he would miss his best friend’s wedding in October because the Mets would be in the playoffs.

The night of that wedding, in fact, a d’Arnaud home run blasted the Apple in Game 1 of the NLCS at Citi Field.

This year is going to be even bigger and better for the Mets, d’Arnaud promised.

No player knows the Mets pitchers better than this catcher, and d’Arnaud is more determined than ever to make the most of 2016.

“I think we’re going to be great,’’ d’Arnaud told The Post on Monday at Tradition Field. “It’s an honor to be involved in all of this. It’s going to be one hell of a year to see what everybody can do.

“The goal this year is World Series again and this time win it.’’

To get the year off right, d’Arnaud rented a 30-foot RV to see America, including witnessing the sun rise at the Grand Canyon on a glorious New Year’s morning — as the d’Arnaud party RV-ed from California to Florida.

“At one point we had eight people on the trip,’’ d’Arnaud said of the four couples that included his brother Chase and his girlfriend, Kaitlyn, Mets minor leaguer Jonathan Johnson and his wife, Shelbie (whose wedding d’Arnaud missed), and Diamondbacks pitcher Kyle Drabek and his wife, Leigh.

“Knocked it off the bucket list,’’ d’Arnaud said of the trip that included stops in Albuquerque, Houston, New Orleans, Panama City, Fla., and Orlando. “It was a blast.’’

His girlfriend, Britney, comes from an experienced camping family, which helped immensely. D’Arnaud, who turns 27 Wednesday, learned much about RV-ing, including how not to dispose of gray water.

“I put the tube in the wrong place,’’ he said with a laugh, an offseason lesson after a year of on-the-job experience working with the Mets’ staff.

“They all have [guts],’’ d’Arnaud said. “They all pitch with their heart. They all pitch with their brain. No one is afraid of anybody. What else would you want from a staff?”

That says it all about young starters Matt Harvey, Jacob deGrom, Noah Syndergaard and Steven Matz, with Zack Wheeler on the way.

“The experience was huge for us,’’ d’Arnaud said. “To not only gain a whole year of baseball but to be able to play in those prestigious months — October and November was tremendous.’’

D’Arnaud learned he has to slow the game down.

“I feel like sometimes I try to do things too fast or too hard, and it got me out of my rhythm and everything was going everywhere,’’ he said of his World Series, in which he hit .143 and the Royals stole seven bases. “Don’t try to be perfect.

“That’s how you learn, from your failures,’’ said d’Arnaud, who hit .268 during the season with 12 home runs, drove in 41 runs and posted an .825 OPS but only played in 67 games because of injuries. He bounced back, crushing three home runs in the first two rounds of the postseason.

Most of all he wants to stay healthy for his pitchers, whom he raved about.

“Syndergaard’s confidence has really grown, and as a result he is no longer overthrowing his pitches,’’ d’Arnaud said. “Instead of throwing 102 [mph], why not just throw 100.’’

Of Syndergaard’s sending a message pitch in the World Series, d’Arnaud was onboard.

“You got to trust your pitchers, and he’s a big corn-fed Texan. He’s fearless.’’

As for Harvey, d’Arnaud said: “That comeback was unbelievable. It could have been a career-ending surgery, and he shook it off like nothing and was dominant from his first game.’’

D’Arnaud said one of the most impressive aspects of deGrom’s game is not only his electric arm, “but he is so even-keeled that he just shakes off everything. He’s like Bartolo [Colon] in that respect.’’

He compared Matz to Syndergaard, saying: “He is learning to trust his stuff, too. And learning that his 94-95 is still a plus-plus pitch compared to trying to throw 96 and leaving it over the middle.’’

D’Arnaud said he is often asked by opposing hitters, “ ‘How would you rank these guys?’ I tell them it’s hard for me because they all throw 95-plus.’’

That’s why d’Arnaud is expecting even greater accomplishments in 2016.

This should be some ride across America for the Mets.