It didn’t really dawn on Leo Kottke. The Twin Cities guitar hero doesn’t really think in a conventional, linear fashion. He didn’t even realize he was changing his annual Thanksgiving time concert routine in his hometown.

In his 35 years of playing a turkey weekend show, he has never done one on Black Friday. He mostly has performed on Monday.

Kottke’s longtime manager “doesn’t like playing on Mondays,” the guitarist said. “As a promoter, it’s just impossible to sell tickets.”

But Black Friday?

“It won’t be like competing with the Super Bowl,” Kottke observed. “But it might be close.”

And he has never headlined at the Fitzgerald Theater in St. Paul, where he will do so on Friday, although he has performed in the theater as part of Garrison Keillor’s “A Prairie Home Companion.”

“It is the most nerve-racking thing I do,” he said of Keillor’s live radio show. “It’s like catching a moving train. Garrison will throw you a curve. The last one I did he gave me a long set of stanzas and he wanted me to put it to music and sing it. And I couldn’t scan the stanzas. In the end, it worked out.”

Having a conversation with Kottke is a lot like experiencing him in concert. You don’t know what’s coming next — and neither does he. It could be something about his music, a person he met in his travels or an odd factoid gleaned from books he has read. Oftentimes he’ll manage to tickle your funny bone with a wicked one-liner.

Kottke, 70, doesn’t like to be predictable. He likes performing without a net.

“If I ever eliminate the risk of falling flat on my face, I’ll lose all,” he said. “So I kind of have to befriend terror.”

Thus, he never prepares a set list for a concert. He does try to choose an opening song about a half-hour before showtime but often changes it as he walks to the stage. After the opening number, he wings it, which is pretty much how he approaches life.

“I don’t have a routine. It’s something I’d like to [have]. I’m told the human body prefers predictability. One of my big routines to keep my mind intact is to try to remember what I had for breakfast,” he said over lunch recently in downtown Minneapolis.

Um, he couldn’t remember.

Even though he doesn’t have a routine, he does have rules.

No visitors backstage before the show. He needs to get into a zone and sometimes prefers to sit in darkness.

He has two rules of do’s: Perform some songs with vocals (“I enjoy them a lot more now than I ever have”) and play some slide guitar.

And he has two rules of don’ts: Don’t talk politics onstage and don’t play unrecorded songs in concert.

In 2008, he performed a new, unrecorded song called “Ants” in concert, and it ended up on YouTube.

“It was the first or second time I played it, and it’s not done at that point,” said Kottke, whose last album was 2005’s “Sixty Six Steps” with Mike Gordon, Phish’s bassist. “It’s a work in progress. So I don’t play it. I will once I get it recorded.”

So is he doing a new album?

“I don’t like recording, but I’ve got to do it so I can play the new stuff onstage,” he said.

Kottke has written 14 songs. “That’s a lot more than I usually have,” he said. “I’m actually writing a lot of vocals now. They come in bunches, but they don’t come as often as instrumentals.”

Phishing for new album

Kottke is talking about recording again with Gordon — and possibly Phish drummer Jon Fishman and drummer Brian Blade. But no sessions are scheduled — and Kottke doesn’t have a recording contract.

Kottke did fewer concerts than usual in 2015 in order to record and “to see what it’s like.”

“This month, I’m working only four or five nights — and three of them are in Seattle,” said Kottke, who typically drives himself to all his gigs.

Maybe the biggest difference in Kottke’s life is a move to a downtown Minneapolis apartment a few years ago after decades in Wayzata, where he used to tinker with cars and engines in his garage. With no room for tinkering, he reads instead. Voraciously.

Among his recent books are a Stalin biography by Stephen Kotkin and fiction by Joy Williams.

And, of course, with Kottke, there’s always a back story.

“I wasn’t allowed to read as a kid,” he recalled. “If my folks caught me reading, they had a code word: ‘Go outside and get some fresh air.’ They’d make me close the book and leave the house. That’s how I read ‘Huckleberry Finn.’ I’d sneak the book out of the house and sit in some vacant lot in Cheyenne [Wyoming] where the weeds were taller than I was and read.

“So I now have more books than I can handle.”