In 1962, a 17-year-old Stephen Stills rolled tape with an acoustic guitar in hand and recorded one of his first songs. The resulting gospel-tinged folk number, “Travelin’,” features the teen Stills singing in a Pete Seeger-esque falsetto, preaching unity and extolling the virtues of life on the road.

“I been this wide world over, Lord,” he sings, “I been this whole world ’round / I don’t know what I’m looking for / But I know that it can be found.”

Stills seems to have known, even then, as a kid in a military family bouncing around bases in Central America, that he was bound for a peripatetic existence.

Stills unearthed “Travelin’” last year for “Carry On,” an 82-song box set that spans his 50-year career and includes him solo, with Buffalo Springfield and with Crosby, Stills, Nash and (sometimes) Young, among other collaborations.

The capstone collection kicked off a year that showed Stills, now 69, remains a creatively alive artist. He’s still searching, still making new music and still a man of the road.

Last summer he put out an album with his new blues band, The Rides, toured with them in the fall and then hit Europe with Crosby, Stills and Nash in the winter. This spring he’s on a solo tour of the West that brings him to the Belly Up tonight (to be followed by a summer run with CSN).

“I’m younger than the last time I was there,” Stills said with a laugh from his California home. “It’ll be a really good show, including standards, lots of surprises — some that surprise even me.”

His solo show includes two sets with a three-member backing band and an acoustic interlude with just Stills on stage. Along with the many classics he’s penned and new material from The Rides, he says he’s put together treatments of covers that offer his take on songs by each of his CSN bandmates and Bob Dylan.

“I was tempted to do Leonard Cohen,” he said, “but then something said, ‘Your sense of humor is getting the better of you.’”

Of course, seeing an aging rock star in concert can be a dicey proposition. Often it boils down to watching a guy who looks like a pirate and sounds like he’s choking on a barnacle playing tired jukebox-style renditions of his long-gone hits.

To avoid that fate, Stills has never stopped tinkering with the arrangements of his crowd favorites like “Love the One You’re With,” “Woodstock,” “Carry On” and “For What It’s Worth.”

“If you play them like the records, you should shoot yourself,” he said. “I never play them the same way twice, so it’s always interesting — it’s like a jazz band.”

For example, he says, CSN’s “Southern Cross” has these days taken on a reggae sound.

The arrangements also accommodate his voice, which has gotten gruffer and lower in register through the years. At his last Belly Up show — a barn-burning November 2011 performance that showcased his still-virtuosic guitar skills and enduring showmanship — he went for it on one of the highest of high notes in “Suite: Judy Blue Eyes” and hit it, then smirked to the crowd and said something like, “I’m as astonished as the rest of you.”

Stills on Stills

After demurring on writing a memoir and explicitly saying he wouldn’t write one as recently as last year, Stills says he’s now working on a book about his life.

Others have already had their say on Stills in memoirs, including the C, N and Y in CSNY, along with his onetime muse Judy Collins, who inspired “Suite: Judy Blue Eyes” and wrote the memoir “Sweet Judy Blue Eyes.”

Fans can rest assured the fastidious songwriter and guitarist is choosing his words carefully and doing it his way.

“I refuse to have it ghostwritten,” he said. “My aunt that got me straight A’s in English all my life and 800 verbals on my SATs and into college would get out of her grave and slap me silly if I didn’t write it myself.”

Stills says he’s between a third and fourth draft on the book and writing during his breaks from the road.

“It’s real drudgery to write a real book,” he said. “The worst part of it is that it’s about me. I don’t want to write about me. I’d like to make shit up.”

He no doubt has stories to tell, from Altamont to Woodstock to his uncanny knack for collaboration. His musical partnerships, along with the immortal pop harmonics of CSNY and the folk rock of Buffalo Springfield, include Manassas with Chris Hillman (where Stills wrote “Colorado,” arguably the most enduring Centennial State anthem that’s not in the John Denver catalog) and sessions with Eric Clapton, Jimi Hendrix, Ringo Starr and Jerry Garcia.

It’s safe to assume there’s a lot we don’t know about Stephen Stills despite his half-century in the public eye. He’s released upward of 250 songs over the past 50 years, and yet he continues to unearth stuff worth considering, like a recently unveiled 1970 recording session with Hendrix and the 25 unreleased songs and alternate takes included in his box set.

Stills On Aspen

Stills was a frequent Aspen visitor and skier once upon a time, he says, coming regularly for shows but also on visits to ski and see friends like Hunter Thompson and Don Johnson. Now he says he’s “one fall away from knee replacement” and only comes through on tour.

“I miss that big, long Ruthie’s Run, I’ve got to say,” he sighed. “I miss coming to Aspen. I used to come there a lot.”

Hitting a high-altitude venue also offers a regular status check on his voice.

“Once you can make all the high notes in Aspen, it’s all smooth sailing from there,” he laughed. “It’s get in shape or die.”

This time around, he’s scheduled a day off before the show to acclimate and, he hopes, to play a round of golf. He’s not shy to rip Aspen as “the last place in America where it’s OK to wear furs,” but he says concerts here in the offseason tend to take on a certain flavor he enjoys.

“It’s nuts,” he laughed, “especially in a sort of betwixt-and-between season where all the ski-patrol guys are off and they tend to gravitate to the front of the stage and then the hoi polloi from the neighborhoods are in the back.”

Seeing a legend such as Stills in a 450-venue like the Belly Up is a bucket-list-worthy item for many music fans. For him, playing a stage so much smaller than he’s accustomed to can be problematic, Stills says, but worth it.

“We always complain,” he said. “But then we get there, and it’s great.”

There’s Something Happening Here

Stills’ early output is inextricably tied to the social upheaval of the U.S. in the Vietnam and civil-rights-movement era, and he’s remained vocal for progressive causes throughout his career.

Who knows whether it’s a comment on Stills’ timeless songwriting or on the 21st century’s dearth of artists willing or able to make resonant political music, but nobody has written a song about the War on Terror, Occupy Wall Street or PRISM that said anything Stills didn’t already say better in “For What It’s Worth.”

“Becoming a professional protest songwriter is not a vocation,” he said. “We’re chroniclers. We’re descendants of the first journalists.”

Stills calls it unfortunate, however, that songs like “For What It’s Worth” are still relevant in 2014.

He quickly gets riled up talking politics, saying he’s hopeful Sen. Mitch McConnell gets ousted this fall and that more states follow Colorado and Washington’s lead on marijuana legalization.

For years, Stills hasn’t drunk alcohol or smoked pot (“I turn into a lamp or a chair”), but he’s curious to see how legalization is working here.

“I’m interested to see how the great experiment is going in Colorado,” he said. “We’ve been trying to explain it to everyone out here in California. (Gov.) Jerry Brown is all concerned, saying if everybody is stoned nothing will get done. And I go, ‘Yes, and … ’”

These days, Stills’ activism is mostly focused on autism, a cause he’s pursued with his wife, Kristen, as they’ve raised a son with the disorder.

“It’s just a new class of people, and we should get to know them,” he said. “We have more to learn from them than they do from us, because they don’t have filters and they have absolutely no interest in being cool. It’s a great step forward in mankind. Being cool is overrated.”

For the past two years, Stills has organized an all-star benefit concert — modeled after Neil Young’s long-running Bridge School Benefit — for the autism science and advocacy nonprofit Autism Speaks.

A video of this spring’s concert, he points out, topped YouTube’s music videos briefly.

“There was Justin Bieber, Springsteen and us, and we were beating Justin Bieber for a week — the irony!” he said.