3Color Method

The 3Color Method is a unique solving method developed completely independently by Michael Feather in 1980. The method name is derived from the 3Color Cube, which is a Rubik's Cube having tricolor scheme that uses the same color on opposite faces.
Contents
Steps
There are 2 steps for a 3Color Cube and 4 steps for a 6Color Cube with the same list of algorithms (for detailed explanation of algorithms see External Links section).
Solving the corners
1. Orient corners. Either think of the puzzle as a 3Color Cube (i.e. Red=Orange, Blue=Green, Yellow=White in case of BOY color scheme) and solve corners as such, or think of the puzzle as a 6Color Cube and orient all corner stickers in a way that they are matching either the center color or that of the opposite face.
2. Permute corners on a 6Color Cube, three possible cases can be reached using half turns only:
2a. Corners can be solved in both layers.
2b. Corners can be solved in one layer, diagonal swap of corners is required in the other layer.
2c. Corners can be solved in neither layers.
Convert 2b or 2c to 2a using an algorithm (Michael Feather calls them Waterwheel Sequence for 2b and Parallel Sequence for 2c), then continue by solving the edges (or apply 2a first and continue by solving the edges).
Solving the edges
3. Orient edges. Either think of the puzzle as a 3Color Cube and solve edges as such, or think of the puzzle as a 6Color Cube and orient all edge stickers in a way that they are matching either the center color or that of the opposite face.
Use only half turns and/or cube rotations as setup moves between all solving sequences.
After finishing this step, a 3Color Cube will be solved and a 6Color Cube will be solvable using half turns only.
4. On a 6Color Cube, restore corners and permute edges.
Pros
 Low number of algorithms
 Short algorithms; average number of moves per algorithm: 5.7 in STM
 Room for improvement of a move count; current average move count in STM for step 1 ~ 14, for step 2 ~ 9 (or ~ 12 with applying 2a), for step 3 ~ 31, for step 4 ~ 17
Cons
 Thinking of a 6Color Cube as a 3Color Cube could seem rather unintuitive at first
 It's not always possible to exactly match the setup for a solving sequence
 Not suitable for speed solving
Example Solves
Similarities with Human Thistlethwaite Algorithm (HTA)
While the 3Color Method is very different from HTA, there are some obvious similarities in that both start by solving as a 3Color Cube and both finish by reaching a configuration that can be solved with half turns only. The 3Color Method can be modified to work a bit more like HTA by doing the following.
After solving the corners on two opposite faces (like the 3Color Starter Cube), instead of solving the corners on the remaining faces, solve the edges on the two faces with the solved corners.
An advantage of doing it this way is that after solving the corners & edges on two opposite faces (as 3Color Cube) the setups for the 3color edge sequences can always be matched exactly when solving the rest of the cube, no need to make partial matches where only some of the misplaced facelets/stickers get fixed. Another advantage is that the cases in which no misplaced facelets can be fixed are avoided.
One other difference is with the solve order of 6color corners in relation to 3color edges. When solving this way, the corners should only be solved after the edges otherwise the above advantages have exceptions.
See also
External Links
 Home page of the 3Color Method by Michael Feather. Resource of algorithms, tips, advanced solving approaches & more.