Steps
First Block
Build a 1x2x3 block anywhere on the cube. (Largely intuitive)
Second Block
Build a second 1x2x3 block opposite of the first 1x2x3 block, without disrupting the first 1x2x3 block. After this step, there should be two 1x2x3 blocks: one on the lower left side, and one lower right side, leaving the U slice and M slice free to move.
Second Block
Simultaneously orient and permute the remaining 4 corners on the top layer (U-slice). You can use CMLL, COLL, or Corner OLL's (along with the T or J, and Y permutation) to do this.
LSE
Orient the 6 remaining edges using only M and U moves (UF, UB, UL, UR, DF, DB need to be oriented correctly). Solve the UL and UR edges, preserving edge orientation. After this step, both the left and right side layers should be complete. Solve the centers and edges in the M slice. (Largely intuitive)