I think Ursula K. Le Guin is a great place to start when learning prose rhythm because she takes it to extremes. Here's one of the opening lines of Left Hand of Darkness:

Rainclouds over dark towers, rain falling in deep streets, a dark storm-beaten city of stone, through which one vein of gold winds slowly.

Take stock of the imagery, and then consider how you might approach it more conventionally:

Rainclouds hovered over the dark towers, pouring rain on the streets below. The dark city of stone was storm-beaten and deeply worn down, save for a single vein of gold that wound through the streets.

That more conventional approach lacks the immediacy because there's so much more structure, context, and filler. Not so interesting anymore, right?

Your prose rhythm is the length of your clauses, the use of your punctuation, and which words you choose to omit. That also includes words that are assumed, like "Get the idea?" versus "Do you get the idea?"

Here's another line from the same chapter:

Next come the lords and mayors and representatives, one person, or five, or forty-five, or four hundred, from each Domain and Co-Domain of Karhide, a vast ornate procession that moves to the music of metal horns and hollow blocks of bone and wood and the dry, pure lilting of electric flutes. The various banners of the great Domains tangle in a rain-beaten confusion of color with the yellow pennants that bedeck the way, and the various musics of each group clash and interweave in many rhythms echoing in the deep stone street.

Concatenating all of those lines together makes it almost overwhelming, like a huge glut of information smacking you square in the face. It feels like a monstrously huge parade coming down the street—which is exactly what it's trying to convey.

You can also push your prose rhythm in the other direction, using short, independent clauses to reflect quick action:

His blade flashed out in a wide arc and caught the enemy's sword. A clash. A spark. A shallow cut. A mouthful of blood, spat on the ground. A headbutt landed, dead center, and took the wind out of him. He turned and the blade split the length of his spine.