I've watched Fred Couples, and played a round with him ages ago at an event, and watched him out in CA at several events. Fred says he has always had a "lazy looking swing" and thus it looks fluid, and we all marvel at the fluidity. If you watch Fred, he lumbers around between shots, shoulders back, relaxed, like he's shopping at a mall.
Since I have followed Fred over many decades, I have found that my best rounds are when I feel carefree, and walk with excellent posture, and act like I'm just playing a game. So many of us get all TENSE and lose our fluidity during a round, it becomes "work", not "play". My advice is to walk around like a peacock and stop worrying about every shot. IMO there's something to being relaxed and having fun vs. "working" golf.
It's poetry in motion.
Also, it's been said that is the best posture for walking the course (shoulders back, chest out, "peacock-style"). Watch a PGA Tour event in person and you'll see a lot of players doing that.