1) Stop all application services (keep the database and the database listener up and running)
2) Download the patch from Metalink
3) Copy the patch file to any directory (i.e. /u04/patches)
4) As 'applmgr' do the following:
- Source the environment file
- Issue "adadmin" and Select (5. Change Maintenance Mode), then (1. Enable Maintenance Mode)
- $ cd /u04/patches
- Type 'unzip (patch_number).zip'
- cd (patch_number)
- Type 'adpatch'
- When it prompts you to enter the patch driver, type 'u
5) Apply the patch on the database tier first then on the application tier.
6) Once you apply the patch successfully, 'Disable Maintenance Mode' from adadmin.
Note- And, always follow the steps in the patch README file.