STEP-7

STEP-1 STEP-2 STEP-3 STEP-4 STEP-5 STEP-6 [STEP-7]

Step 7-Orient the top layer Corners

Let us take a break and do a little analysis.
Consider the sequence (D'-R'-D-R)x2.

Observe that in the top layer, we have twisted only the front-right corner clockwise and all the other cubies are intact.But we have arbitly spoiled the first two layers.
If we undo the moves we will again get back a solved cube.
But wait! What if we do a U turn and then undo the moves?

Such manipulations are called as "Commutators"
So if we want to turn 3 corners clockwise, then the moves would be:

Congratulations! You have solved the Rubik's Cube!