To get event content to edmDumpEventContent of your AOD file
  edmDumpEventContent 06688145-E89E-E211-9845-002590593876.root
For only info on certain type use regex
  edmDumpEventContent 06688145-E89E-E211-9845-002590593876.root --regex gen

  Type                                  Module                     Label      Process   
  --------------------------------------------------------------------------------------
  GenEventInfoProduct                   "generator"                ""         "SIM"     
  vector<int>                           "genParticles"             ""         "SIM"     
  vector<reco::GenJet>                  "ak5GenJets"               ""         "SIM"     
  vector<reco::GenJet>                  "ak7GenJets"               ""         "SIM"     
  vector<reco::GenJet>                  "kt4GenJets"               ""         "SIM"     
  vector<reco::GenJet>                  "kt6GenJets"               ""         "SIM"     
  vector<reco::GenMET>                  "genMetCalo"               ""         "SIM"     
  vector<reco::GenMET>                  "genMetCaloAndNonPrompt"   ""         "SIM"     
  vector<reco::GenMET>                  "genMetTrue"               ""         "SIM"     
  vector<reco::GenParticle>             "genParticles"             ""         "SIM"     
  vector<reco::Track>                   "generalTracks"            ""         "RECO"    
First column is the name of the class, second is the label.
Google your class reference to see the functions of the class. For instance "reco::GenParticle reference" gives you the page [[https://cmssdt.cern.ch/SDT/doxygen/CMSSW_5_3_6/doc/html/d5/dd4/classreco_1_1GenParticle.html| reco::GenParticle class reference]].
You then need you own analyzer. Check out [[https://twiki.cern.ch/twiki/bin/view/CMSPublic/WorkBookWriteFrameworkModule|Writing your own EDAnalyzer]].\\
For examples, check out  /shome/jngadiub/TestPAT/CMSSW_5_3_11/src/Demo/MyEdmNtupleProducer/src/CandGenParticlesProducer.cc.\\
To get your class
  edm::Handle<reco::GenParticleCollection> genParticles;
  iEvent.getByLabel(genSrc_, genParticles);
To loop
  for(size_t i = 0; i < genParticles->size(); ++i ) 
  {    
    const reco::GenParticle          & ParticleCand = (*genParticles)[i];
    const reco::GenParticleRefVector & motherRefs   = ParticleCand.motherRefVector();
    const reco::GenParticleRefVector & daughterRefs = ParticleCand.daughterRefVector();
  }
To for instance get eta and pt
  ParticleCand.eta()
  ParticleCand.pt()