There are a few general guidelines that can help get your machine started which are mentioned above, regardless of the OS the user prefers.

It should contain an OS X installer or a usable operating system to work with.

The USB drive should be formatted with a supported GUID partition.

It is advised that the user should go with a USB 3.0 supported drive, with a size of 16GB to ensure a swift transfer of data.

Make sure to purchase the C port flash drive to avoid any inconvenience.

A 12' Mac only contains a single C-Type port.

The user should check to see what size of ports they have on the Mac.

The user should scan the flash drive with some reputable Anti-Virus software.

The USB should contain 16-32GB of free space.

The user should buy a name-brand flash drive.

To ensure a risk-free procedure certain measure should be taken:

By installing older versions through USB, it permits certain Apps to run which are not compatible with the latest macOS.

Allows risk-free testing of the Beta version.

It allows the user to test a new version before you make the decision to upgrade.

Allows the user to install a different version of macOS.

Here are the top reasons why the user should choose to Boot Mac from USB: It also helps to repair the Mac disk with Disk Utility and other tools. It provides the user access to the contents of the internal drive, assuming the data is safe and not corrupted. Using an external source like the USB drive helps the user get around the problem.

The likeliest of the reason for choosing the boot from the USB method is that your Mac won't start which denies the user access to the computer. Reasons for Mac Boot from USBīooting the Mac from USB in a way gives the power back to the user. One of them includes Booting the Mac from such a device. This small tool has opened the world to a stream of limitless options with respect to storing, transferring, copying data, and much more. Thanks to their portable nature, affordability, and compatibility, USB drives are being used to send and receive endless information across a surplus of networks and platforms all around the globe. Today, these drives are one of the most consumed used devices in the world. The drives are available in various sizes and as of to date, the 2TB(Tera-Byte) flash drives in terms of storage capacity are the largest ones available in the market. Any sort of data can be stored in this device.

It is typically removable and much smaller than an optical disc. A Universal Serial Bus or USB Drive, also known as a flash drive is a portable data storage device that includes a memory which includes a USB interface.

Boot into disk utility for mac