DES F-function problem

after all the s-boxes is done, their output goes into P permutation

i dont understand the P table at all...

say i have a output from s-boxes of 1110 1111 1010 0111 0010 1100 0100 1101

how do u permutate it in the p table? please tell me in detail how u do it? i m very lost

P 16 7 20 21 29 12 28 17 1 15 23 26 5 18 31 10 2 8 24 14 32 27 3 9 19 13 30 6 22 11 4 25