To do this, you will need to extract the Access Key and Secret Access Key from the file downloaded in Step 4 of the section creating a new user in IAM:

$ more credentials.csv
User Name,Access Key Id,Secret Access Key
"Nat",AKIACZ6HA,f6hoyLgExmoq/V4VQjf3nB

We will run the following command to configure our AWS account, as follows:

$ aws configure
AWS Access Key ID [None]: AKIACZ6HA
AWS Secret Access Key [None]: f6hoyLgExmoq/V4VQjf3nB
Default region name [None]: us-east-1
Default output format [None]: 

At this point, we are ready to start using the CLI. We can quickly verify that everything is working by listing the user accounts, as follows:

$ aws iam list-users
{
    "Users": [
        {
            "UserName": "Nat",
            "PasswordLastUsed": "2017-07-30T03:11:30Z",
            "CreateDate": "2017-07-28T09:23:50Z",
            "UserId": "AKIACZ6HA",
            "Path": "/",
            "Arn": "arn:aws:iam::511912822959:user/Nat"
        }
    ]
}