Lining up the yellow cross

A cross, but a crooked one

There's a yellow cross on top, just as we left it last chapter. Now look at its edges from the side. Besides the yellow, each one has a second sticker, and that sticker should match the center of its face, exactly as on the white cross down below. Here not a single one does.

Why not drop an edge down and bring it back up, the way we did with the white cross? Because the first two layers are already solved underneath, and a half turn of a side face would wreck them. You need a move that rearranges the edges on top and then puts the bottom back exactly as it was.

Don't worry about the corners yet. They're jumbled and twisted every which way, and that's fine. They get the next two chapters all to themselves.

First, turn the top

Start by turning the top layer, and after every quarter turn, count how many side stickers match their centers. Stop at a position where at least two edges match. There's always one. You could prove it, but it's quicker to take our word for it and start turning.

Here it takes two quarter turns, U2, and then the front and right edges match. Two matching edges are either neighbors, as here, or opposite each other, and each case has its own recipe.

And if all four match at once, congratulations: this step is already done, so skip ahead to the corners. You'll never see exactly three. If three edges are home, the fourth has nowhere else to go.

Two neighbors: park them at the back and right

Turn the whole cube so the matching pair sits at the back and on the right. Here the pair is at the front and right, so that's a y'. Then:

R U R' U R U2 R' U

This swaps the front and left edges and leaves the back and right ones where they are. The first two layers come through intact.

The corners get shuffled along the way too, which is why we've grayed them out. Ignore them: they're next in line.

Why front and left? The algorithm is all right hand, and each turn of the top carries the edges around in a circle. By the end, the back and right edges have traveled all the way around and come home, while the front and left ones have traded places. So you park the matching pair where the algorithm can't touch it: at the back and right.

Meet Sune

The algorithm is seven moves, R U R' U R U2 R', plus a final U. Those seven moves have a name of their own: Sune. It's among the most famous algorithms in all of cubing; just about anyone who has ever solved for speed knows it.

Its rhythm makes it easy to remember: R U R' is a short dip of the right hand, U is a pause, and R U2 R' is a longer dip. The final U in our version simply finishes the job, turning the top so the edges line up under their centers.

You'll meet Sune again in the CFOP chapter, where speedcubers use it to twist corners yellow side up.

Sune in your fingers

Cubers love Sune for another reason, too: it feels good in the hand. You play it entirely with your right hand, with almost no regrips. R and R' are turns of the wrist. U is a flick of the index finger along the front edge of the top face, from right to left. U2 is two quick flicks: index finger, then middle finger right behind it.

Try it on your own cube, slowly and evenly, like practicing scales. If your fingers get tangled, break the algorithm into three chunks — R U R', U, R U2 R' — and drill each one on its own. At first you'll think about every move. Ten repetitions later, your fingers know the way by themselves, and the whole thing takes a couple of seconds.

Two opposite edges

Here the front edge matches, and so does the back one, hidden behind the cube. They're opposite each other, so there's no way to hold them "at the back and on the right." The fix is simple: play the algorithm once, from any angle. It swaps two edges, which breaks up the opposite pair, and a neighboring pair appears in its place.

Then turn the top again. On this cube, one U' makes the front and right edges match: a neighboring pair at last. Rotate the whole cube with y' to bring it to the back and right, and play the algorithm one more time.

Where people trip up

• Parking the pair in the wrong place. The matching edges go at the back and right. Front and left is where the swapping happens.
• Checking the wrong sticker. The yellow on top looks the same on every edge. It's the side sticker you need to read.
• Turning the whole cube instead of the top while hunting for matches. You hunt with U: the centers stay put and the edges ride around. But once you've found your pair, you turn the whole cube to bring it to the back and right.
• Panicking about the corners. They're supposed to be scrambled.
• Dropping the final U. Without it, the top ends up a quarter turn off, and it looks as if nothing matches. If that happens, just give the top that last quarter turn.

Try it yourself

Get all four edges of the yellow cross under their centers. First find the turn of the top that makes two edges match. You know the rest.

Next: the corners

The edges are home, and the cube looks almost solved. Almost: the corners on top are mixed up, with their yellow pointing all over the place.

We'll handle them in two passes. First, each corner goes to its own spot, whichever way its yellow happens to face. Then, in chapter 9, we'll twist them the right way up and see the most beautiful trick in the whole course.