Click on "Applications" and find the folder called "Utilities". In the "Utilities" folder find the "Disk Utility.app". Double Click that application to start the utility. The volume type should be "Mac OS Extended". You can select the partition from the drop down menu on the right hand side. When formatting please do not adjust the size of the disk, simply have it re-format the entire volume with a single partition.

Luckily OS X will not let you format an active drive, but do be careful that you are formatting the correct volume in order to protect against possible data loss especially if there are multiple storage devices attached.

In order to activate Time Machine please enter the "System Preferences". The Time Machine icon is located in the system section. Double click the Time Machine icon to attivate the window. Once the window has opened you will be able to select which hard drive (if you have multiple drives) you would like to use as the Time Machine backup drive. Once you have selected the drive click the switch to "On". Once active, Time Machine will let you know when the backup will take place (typically one hour after being activated), and it will do an incrimental backups of any data that has changed every hour after that.

To search through the backup files you will need to enter the "Applications" folder and double-click "Time Machine.app". Once the applicaiton is active the desktop will slide out of view and the Time Machine console will be active. The control visible on the right hand side will allow the user to view the backups going back through time. The controls along the botton will allow the user to either restore the needed file or to cancel the seach all together.