Quoted from cern twiki, refer to the slides for some changes in the setup (considering the powheg.input and Born_phsp.f files):

Download POWHEG and bbH process folders
     svn checkout --username anonymous --password anonymous svn://powhegbox.mib.infn.it/trunk/POWHEG-BOX-V2
     cd POWHEG-BOX-V2
     svn co --username anonymous --password anonymous svn://powhegbox.mib.infn.it/trunk/User-Processes-V2/bbH
     cd bbH

Compile it
    1. setup compiler with command "cmsenv" issued for example, in CMSSW_8_0_22/src
    2. in bbH folder edit Makefile to provide link on CMS lhapdf-config:
          LHAPDF_CONFIG=/cvmfs/cms.cern.ch/slc6_amd64_gcc530/external/lhapdf/6.1.6/bin/lhapdf-config

    3. if you run on lxplus use in Makefile
          OPT=-O0 
       after line  
          ifeq ("$(COMPILER)","gfortran")
    4.  to have YR4 QCD scale copy to your bbH dir: cp /afs/cern.ch/user/a/anikiten/public/POWHEG/Born_phsp.f .
    5. compile with command: make pwhg_main

produce lhe event file
    1. go to testrun directory under bbH directory
    2. cp /afs/cern.ch/user/a/anikiten/public/POWHEG/powheg.input
    3. change the Higgs mass as you like in powheg.input and modify accordingly hdamp: hdamp = 1/4 (mH+2mb); change Higgs width as you like.
    4. generate event with command:  ../pwhg_main either in parallel mode (4 steps with changing in powheg.input parameter, parallelstage  1, 2, 3, 4) or in one shot:  parallelstage 0; see manual)