There are some rules(formulae) At first you need to make a plus sign in the third layer. Plus = F R U R' U'F' ( you have to apply this formula until you make a plus sign, maybe twice, thrice or once ) THEN Match centres = R U U R' U' R U' R'
Place Corners= L U R U' L' U R' U'
Last Step= R U U R' U' R U' R' L U U L' U L U L' (you have to apply all these formulae until you make the mentioned position, maybe twice, thrice or once. ) Thank you ..