Macbooks or iMacs hardly require reinstallation of their Mac OS, but when they do it is quite a difficult process especially if your secondary computer is Windows. Below I will list you 2 ways to create Mac OS bootable USB drive on Windows.
Before you start make sure you have :
A USB stick with at least 8 GB of memory (16 GB recommended).
An ISO or DMG installation image of a version of Mac OS (you can find them at this link).
This guide is valid only for versions after 10.5 .
Download the latest version of TransMac from this link.
Once downloaded connect your USB drive.
On TransMac right click on the USB drive and select " Format disk for Mac ".
Next, right-click the USB drive again and select" Restore with disk image ".
At this point click on the " Add " button and from the window that will appear at the bottom right change from " Disk Image files (* .dmg) " a" All files (*. *) ". Now choose the .dmg or .iso file you downloaded earlier.
TransMac will create a bootable Mac OS USB version in a few minutes.
Once finished , insert the USB stick on your Mac , hold down the " option " key while it powers up and boot the system with the USB drive.
An alternative to TransMac is PowerISO, a simple program to create bootable USB drives of any type.
Once installed, open it and insert the USB drive into your computer.
Now import the DMG / ISO file and click " Burn " in the toolbar.
In the Burn window , select the DMG / ISO file from the " Source File " section (you can change the settings to adjust the burning speed. L default is set to maximum).
You can choose to finalize the di sco and check it. Any errors in the bootable USB will be displayed at that point.
Now click " Burn " and wait for the process to finish.
Once finished, insert the USB stick on your Mac , hold down the " option " key while it powers up and boot the system with the USB drive.