Put them in /net/sw/mosis/downloads. Inside the kit file, there’s usually a file called kit_install. Just run that and follow the prompts.

[mary@server1 CMRF8SF_DM_Assura_QRC]$ ./kit_install

  IBM Design Kit Install Utility

  This shell script installs IBM Design Kits from a directory containing
  the distribution files to a specified destination directory .

  Enter your installation path up to but not including IBM_PDK: 
  /net/sw/mosis

  This package contains components or add-ons for any base release (V1.5.0.x).

  Continue with install? Enter Yes or No (y|n): y

  The distribution files are located in: /net/sw/mosis/downloads/CMRF8SF_DM_Assura_QRC
  Enter Yes or No (y|n): y

  No  "rel" symbolic link was found.  Do you want to create
  the "rel" symbolic link to point to V1.5.0.0DM (useful for PATH
  statements)? This is optional.
  Enter Yes or No (y|n): y

  You have a kit with an option.  Would you like the symbolic
  link recognizable as "relDM" and NOT "rel" : 
  Enter Yes or No (y|n): y

  *** Install package(s): 
         cmrf8sf_CadenceQRC.V1.5.0.0DM
  *** Install to directory: /net/sw/mosis/IBM_PDK/cmrf8sf/V1.5.0.0DM
  *** Install from directory: /net/sw/mosis/downloads/CMRF8SF_DM_Assura_QRC
  *** Set up symbolic link "relDM" to link to V1.5.0.0DM

  Do you wish to continue? 
  Enter Yes or No (y|n): y


  After successful installation, you may delete the distribution
  files from /net/sw/mosis/downloads/CMRF8SF_DM_Assura_QRC to recover space.

  *** Installing cmrf8sf_CadenceQRC.V1.5.0.0DM *** (this may take several minutes)
  Installation of cmrf8sf_CadenceQRC.V1.5.0.0DM Complete

  Update /net/sw/mosis/IBM_PDK/cmrf8sf/V1.5.0.0DM directory? 
  This will update the appropriate kit files with your .
  Enter Yes or No (y|n): y

  Path update script has been run with the following message:

   Updating files in /net/sw/mosis/IBM_PDK/cmrf8sf/V1.5.0.0DM/


  Symbolic Link "relDM" set to V1.5.0.0DM

  Moving /tmp/.install_log_cmrf8sf.V1.5.0.0DM.CadenceQRC_by_mary_on_03.23.09.29.13
  to /net/sw/mosis/IBM_PDK/cmrf8sf/V1.5.0.0DM

  Moved  /tmp/.install_log_cmrf8sf.V1.5.0.0DM.CadenceQRC_by_mary_on_03.23.09.29.13
  to /net/sw/mosis/IBM_PDK/cmrf8sf/V1.5.0.0DM