Steps to Cloning a Database

The following steps must be on Source -Production instance/Server
Step 1. Shutdown database in normal mode and start it up in restricted mode.
Step 2. Take the backup of control file
Step 3. Shutdown database again in normal mode.
Step 4. Copy /FTP init parameter file ,control file script and all the database file on the destination server/location, once all the files are successfully copied, you may startup the database normally.The following step must be on destination – Clone instance/server.
Step 5. Edit init parameter file and control file script.
Step 6. New Environment setup .
Step 7. Connect with svrmgrl and recreate control file.
Step 8. Open the database in resetlogs.
Step 9. Shutdown the database in normal mode
Step 10. Take the cold backup and start the database in archive/non archive mode.
Details :-

Step 1 – 3 on the Source Server ( Server A)
SQL> connect sys/pass
Connected.
sql> shutdown ;

Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup restrict
ORACLE instance started.
Total System Global Area 57124108 bytes
Fixed Size 70924 bytes
Variable Size 40198144 bytes
Database Buffers 16777216 bytes
Redo Buffers 77824 bytes
Database mounted.
Database opened.
SQL> alter database backup controlfile to trace;

Statement processed.
SQL>
SQL> show parameter user_dump_dest
NAME TYPE           VALUE
----------------------------------- ------- -------------------------
user_dump_dest         string E:\ora816\admin\ora816\udump
Note :- Backup control file will generate in user dump destination as above. Check for the latest Ora.trc . Rename this file to Ctrlprod.sql