Backup Schedule

I'm getting a new Laptop next week with Win 7 Home Premium 64 Bit (OEM)

I've been reading up about Back up and Restore

If I want to Backup a System Image or Data Files, can I do this as and when I want to or is setting a Schedule compulsory?

The reason for my question is that I want to Backup onto an External HDD which will not be permanently plugged in, normally I just plug it in when I want to use it

If Setting a Schedule is compulsory then I would have to remember when it was due and make sure the HDD was plugged in at the right time?

Also, it's difficiult to Set a Schedule if the Laptop is turned off when not in use?

I would like to do a Backup as and when I want to, is this possible?

Thank you

Thingy,
Refer "Limitations" -
Backup and Restore Center - Wikipedia, the free encyclopedia

Manual image-based full system backup (including incremental backup) can be done on local or removable media in Windows 7 Home Premium.

Click to expand...

Some links for you to peruse.

http://www.sevenforums.com/tutorials/663-backup-complete-computer-create-image-backup.html

http://www.sevenforums.com/tutorials/615-backup-user-system-files.html

http://www.sevenforums.com/tutorials/618-backup-files-schedule-turn-off.html

http://www.sevenforums.com/tutorials/82372-backup-cd-dvd-enable-disable.html

http://www.sevenforums.com/tutorials/82379-backup-local-hard-disks-enable-disable.html

Thank you - your third Link answered my question