Full Database Recovery or Disaster Recovery.

You use the RESTORE and RECOVER commands to restore and recover the database.RMAN checks last good backup set and restore the datafiles to the state they were in when that backup set was created. When restoring database files with RMAN, it reads the datafile header and makes the determination as to whether the file needs to be restored.
 
If you cannot restore datafiles to their default locations, then you must update the control file to reflect the new locations of the datafiles. Use the RMAN SET NEWNAME command within a RUN command to specify the new filename. Afterward, use a SWITCH command, which is equivalent to using the SQL statement ALTER DATABASE RENAME FILE, to update the names of the datafiles in the control file. SWITCH DATAFILE ALL updates the control file to reflect the new names for all datafiles for which a SET NEWNAME has been issued in a RUN command.(Restore files to another location will  be demonstrated in another post)

The recovery is done by allocating a channel for I/O and then issuing the RMAN restore database command. The database must be in MOUNT state when restoring or recovering the entire database.

SQL> startup mount;
   or
RMAN> startup force mount;

Then connect to rman and perform:
RMAN> restore database;
RMAN> recover database;
RMAN> alter database open;

Another option with controlfile restoration
SET DBID <database_id>; # use database id from RMAN, not required if using recovery catalog
CONNECT TARGET <target_connect_string>;
STARTUP NOMOUNT;
RUN
{
# You need to allocate channels if not using recovery catalog.
ALLOCATE CHANNEL CH1 TYPE DISK;
# Optionally you can use SET NEWNAME and SWITCH commands to restore datafiles to a new location.
RESTORE CONTROLFILE FROM AUTOBACKUP;
ALTER DATABASE MOUNT;
RESTORE DATABASE;
RECOVER DATABASE;
ALTER DATABASE OPEN RESETLOGS;

Another Method: Restore Spfile and Controlfile
1 Assuming that we have a full backup under /bkp
2 Start RMAN
$ rman target / nocatalog
3 Start the DB (nomount) and restore the pfile
RMAN> set DBID=248804095;
startup nomount;
run
{
restore spfile to pfile '/oracle/product/10.2.0/dbs/initTEST.ora'  from'/bkp/c2488040952009013004';
shutdown immediate;
}
4 Start the DB with the pfile that we just restore:
RMAN> set DBID=248804095;
RMAN> startup nomount pfile = '/oracle/product/10.2.0/dbs/initTEST.ora';
5 Restore the control files
run
{
restore controlfile from '/bkp/c2488040952009013004';
alter database mount;
}
6 Restore the data files
run
{
restore database;
recover database;
}
7 Start the DB
RMAN> alter database open resetlogs;

Use RESETLOGS after a point in time recovery  or recover a database using a backup of the control file. RESETLOGS will initialize the logs, reset your log sequence number, and start a new "incarnation" of the database. 

During the recovery, RMAN automatically restores backups of any needed archived redo logs. If  RMAN restores archived redo logs to the flash recovery area during a recovery, then it automatically deletes the restored logs after applying them to the datafiles. Otherwise, you can use the DELETE ARCHIVELOG command to delete restored archived redo logs from disk when they are no longer needed for recovery. For example, you can enter the following command: RECOVER DATABASE DELETE ARCHIVELOG;