The last steps to solve the 2x2 Rubik´s Cube are shown on this page. If you need a complete guide, then go click the link in the bottom of this page.
Remember to hold the cube so yellow is the UP face while applying the algorithms below.
Solve the yellow side
If there is one yellow tile on the UP face AND one diagonal to the Front face, then you can apply these algorithms:
Front and right: R U R´ U R U2 R´
Front and left: L´ U´ L U´ L´ U2 L
Place the yellow corners correctly
If another face color than white and yellow is solved, then hold the cube so that the color is the BACK face. Follow this algorithm and you will succeed: