By failing to prepare, you are preparing to fail.
Benjamin Franklin (1706-1790)
Preparation involves gathering the appropriate tools, documentation, etc. Implementing covers safely and efficiently carrying out the task. Testing and tidying involves testing that the task has been carried out correctly and tidying up afterwards. Preparation is arguably the most important step in working with computer hardware. Time spent at this stage may result in much larger savings in time later on by preventing and minimising any possible difficulties.
Careful preparation may also prevent damage to the new or existing hardware. This is probably the stage where most shortcuts are made but it would be very good practice, especially for the less experienced, to prepare carefully before starting a task.