Yes, I do this using operating system's job manager, but you can also do it using OEM Management Server. You can use RMAN or other tool, but I just wrote my own code since's I wasn't required to use block level inspection (incrementals backups.)
For example, on Windows you create a Scheduled Task to run every X days. The Windows job must call an executable, such as a .bat file, which can start sqlplus and log into Oracle and run your SQL file, where "your SQL file" is a text file containing the necessary Oracle backup commands that you will build dynamically, spool to a file, and read back into the SQL*Plus buffer.
Remember you can only take hot backups if the database is in Archivelog mode. If you are not sure, connect sys as sysdba then issue command Archive Log List; If the database is not in Archivelog mode, you can still take backups ever X days but they must be cold backups. In that case, your SQL script would simply be a "shutdown immediate" command.