Reduction method: centres, edge pairing, like a 3x3 + two parities. Full course with animations and simulator: strefa-kostek.pl/en/kursy
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1Move notation
RLUDFB - one outer layer, quarter turn clockwise, looking at that face. Rw = two right layers at once, 2R = only the second layer from the right (direction as R). xyz = whole-cube rotation like R, U, F. Order: centres → edge pairing → like a 3x3 (outer moves only) + two parities.
2Centres
A 2x2 square of one colour on a face.
topempty spot in the back-left corner (U)
frontcentre piece in the bottom-right corner (F)
2R U 2R' from the front to the top
2R' D2 2R left half of the bottom ↔ right half of the front (from the bottom to the front)
3Centre order
White on top (the face with the most white). Another side to the front: y.
x2, yellow on top, white on the bottom.
z: white on the left, yellow on the right - they stay on the sides. Rotations only x and y2.
Green on top. Then white on the left (y2), x - green at the back.
Orange on top. Do not touch the back any more.
x: blue on top from the front, red solves itself.
Check: opposite each other white-yellow, green-blue, red-orange; white on the bottom, green at the front - red on the left. Centre swap: see below.
4Edge pairing
Every edge made of two halves with the same colours.
Unpaired edge at the front left (rotate the cube).
The match for its upper half into the front-right edge: from the top U… R', from the bottom D… R, from the back R2 or B2 R2.
At the bottom of the right edge? R U R' F R' F' R flips it.
Both upper halves: same colour at the front and on the side:
Uw' R U R' F R' F' R Uw
5Continue like a 3x3
Yellow on top, outer moves only (R, U, F…).
daisy → white cross
white corners: R U R' U'
second layer: U R U' R' U' F' U F / U' L' U L U F U' F'
yellow cross: F R U R' U' F'
yellow edges: R U R' U R U2 R' U
corners into place: U R U' L' U R' U' L
corner twisting: R' D' R D
6Flipped edge
OLL parity: in the yellow cross 1 or 3 yellow edges facing up.
Hold the edge without yellow on top at the front:
Rw U2 x Rw U2 Rw U2 Rw' U2 Lw U2 Rw' U2 Rw U2 Rw' U2 Rw'
After x you hold the cube in the new position; at the end yellow is on top again. Then the usual yellow cross.
7Two corners in place
PLL parity: in the “corners into place” stage exactly 2 corners are in place.
From any side:
2R2 U2 2R2 Uw2 2R2 Uw2
Swaps the front and back edges of the top. Then go back to the “yellow edges” stage.
At the end only the front-back edges are swapped? The same algorithm finishes the cube.
!When something goes wrong
Mixed-up layers: Rw = two, 2R = only the inner one, R = only the outer one. 2L and Lw turn like L.
A centre piece escapes from the top: before 2R U 2R' the back-left corner of the top must be an empty spot.
Centre swap (best right after solving the centres): two adjacent on the top and front - (2R U2 2R') F2 U2 (2R U2 2R'); red with orange - white on the bottom, green at the front, z, the same algorithm, x2, algorithm, x.
Before turning an inner layer, align the others - the 4x4 locks up easily.
Letter = quarter turn clockwise, looking at that face; ' = the other way; 2 = half turn. Rw = two right layers, 2R = only the second layer from the right.StrefaKostek.pl