Help! Users Folder On Startup Disk?

Hi, I Want To Change The Home Directory Name On My 2011 MBP. I Can't Complete This Step. How Do I Do It?

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Go to the Users folder on the startup drive. The Users folder contains the home folder of the account you're renaming. Rename that account's home folder and make note of both the old name and new name. ''

How Do I Access The Startup Drive?

Thanks, Will