switchover/failover

I have configured 11.2 Active DG with FSFO, Can some one give me the steps for switchover & failover please?
DGMGRL>  show configuration verbose

Configuration - PHOHCM

  Protection Mode: MaxPerformance
  Databases:
    PHOHCM01 - Primary database
    PHOHCMDR - (*) Physical standby database

  (*) Fast-Start Failover target

  Properties:
    FastStartFailoverThreshold      = '90'
    OperationTimeout                = '30'
    FastStartFailoverLagLimit       = '30'
    CommunicationTimeout            = '180'
    FastStartFailoverAutoReinstate  = 'TRUE'
    FastStartFailoverPmyShutdown    = 'TRUE'
    BystandersFollowRoleChange      = 'ALL'

Fast-Start Failover: ENABLED

  Threshold:        90 seconds
  Target:           PHOHCMDR
  Observer:         ukirp293.ukroi.tesco.org
  Lag Limit:        30 seconds
  Shutdown Primary: TRUE
  Auto-reinstate:   TRUE

Configuration Status:
SUCCESS