Are you ready to impress your friends and look like a genius? Using an improved method based off the one supplied by the Rubik's company, you'll soon be solving the cube in under 30 seconds!
The only material you need for this instructable is your Rubik's Cube- so let's go! NOTE: You can view this instructable here, or download the abridged version as a one page .pdf
Use the picture as a guide- ULF would mean turn the Upper layer clockwise, then the Left layer clockwise, then the Front layer clockwise, whereas UL'F would mean turn the Upper layer clockwise, then the Left layer counter-clockwise, and the Front layer clockwise.
Step 1: The Cross
Orient your cube with the white side on the top, and attempt to make a plus (+) sign with white pieces.
Now look at the edge pieces that make up your cross. Align all of them with the correct color of center piece that they touch. (This step is mostly intuitive, but might require flipping the F, R, L, or B layer twice to get the piece to B)
Step 2: Solving the Edges
See the piece between the Red and Green center pieces in the picture below? It's in the wrong place. Orient the cube with the White cross on the bottom, and find a piece in the U layer that doesn't have yellow on it. Turn the U layer until that piece is matched with the center piece that matches its color on the U layer.
From there, orient the cube with those pieces in F. Perform the algorithm L'UL to get the piece in place. Repeat this step only twice more with other pieces.
Step 3: White Corners
Now your cube has 3 of 4 edge pieces in place. Orient the cube with yellow on U, and find a white piece on U. Align that white piece above the mismatched edge piece. Now, look at the other 2 colors on your corner piece. Find the place that piece should go on the D layer. Spin D until that spot aligns underneath the other 2, then turn the cube so that your set-up is on the right side perform RUR' algorithm as many as 5 times to get your piece in correctly. Repeat this step with all corners.
Step 4: The Final Edge
You probably still have the last edge piece to put in. Spin U until the edge piece matches the color to the right of the 2 colors. With this alignment in F, perform U'L'ULUFU'F' if the piece goes in backwards, repeat this process
Step 5: The 2nd Cross
Now, there should be 0, 2, or 4 yellow pieces matching the yellow center piece in U. R'FRF'U'F'UF will toggle the yellow edge pieces in the UF and UR positions yellow side up and yellow side down. Repeat this until you have all 4 yellow edge pieces up.
LUUL'U'LU'L'U' interchanges the edge pieces at UL and UB- repeat as necessary to align all the yellow edge pieces with their proper colors.
Step 6: Yellow on U
There are 4 different situations you may encounter at this point. A 'ÂFish,' a 'ÂDouble Fish,' a normal cross, or a 'ÂCastle.'
If your cube has either just a cross, or a fish pattern like picture one, find the yellow corner piece that when its side was rotated once, would end up in the empty space by it's tail. If, the yellow side of that piece is to the left of the center piece (as shown), orient it with that side to the front, and perform L'URU'LUR' -otherwise, (if the yellow side is to the right of the center piece) perform RU'L'UR'U'L. From there, reassess the pattern using this column.
If your cube looks like picture 2 or 3 (Double Fish/Castle), align it so the side with the arrow pointing to it (relative to the pattern- NOT the color). Then simply perform LFR'F'L'FRF' and re-evaluate the situation to find your next step.
Step 7: The Final Move!
Once you end up with all the yellow pieces facing up, but some in the wrong places, perform this algorithm as many as 3 times: R'FR'BBRF'R'BBRR and you've done it! Congratulations!
Using this method, I've personally solved a cube in under 25 seconds on multiple occasions. Keep practicing- and don't be afraid to try new ideas! Once you get good, you'll want to work on 'finger tricks' -or using your fingers to spin the cube instead of your hands, in addition to keeping the cube oriented with one color on top and solving with any starting color!