Greetings,
High level steps:
Download and extract the appropriate ASE binaries. Run setup. Choose to install only Open Client.
The resulting directory tree structure should be like:
/sybase/ASE-15_0
...
/sybase/OCS-15_0
...
Edit the interfaces file to add the remote entry with the server you need.
Add the SYBASE.sh file to your login sequence e.g. (.profile) to set the path to include the directory with the interfaces file and ISQL in your path.
Regards,
Jean-Pierre