Kali Linux is well established as a starter system for penetration testing, but in the standard configuration it is not ideal for regular desktop usage. While in many scenarios a live boot or a virtual environment can solve these problems, a complete installation is better in some situations. On a Kali Linux desktop, some simple changes can be made to make using it safer in this environment.
Unlike other Linux distributions, Kali was designed only as a penetration test toolkit. This means that while desktop-focused tools such as office suites and games are not neglected, they are not the focus of developers. The distro is primarily configured for temporary use because it is by default set to a single-user mode, which speaks against the best practices for desktop-oriented distribution security. There are a few other common ways to use Kali besides installing a traditional operating system.
The most convenient way to use Kali is when you run it in a virtual machine. Tools such as VirtualBox allow you to use other operating systems in a sandbox environment on a Windows, MacOS, Linux, or BSD host operating system. The limitations of a virtual machine include potentially difficult configurations, increased memory utilization, slower performance, and network hardware issues. Some of these issues can be resolved by running Kali as a live boot.
If you are using Kali as a live boot, you must create a bootable image on an external drive and boot from that device instead of the operating system installed on the hard disk. This provides direct access to the system and network hardware because the additional layer of a host operating system used for virtualization can be bypassed. Kali also offers persistent and encrypted live image options, which means that any work done in a live setup can be saved to the same drive. While this persistence makes Kali very useful as a live system, system performance and disk space can be a problem.
If neither can be used, Kali can also run as a Windows subsystem, if you want to continue using Windows without the need for even a reboot, nor a complete virtual machine environment.
Kali is by no means recommended or ideal for primary desktop use. To quote the Kali Linux documentation:
The fact is, Kali is a Linux distribution designed specifically for professional penetration testers and security specialists, and given its unique nature, it is NOT a recommended distribution if you are Unfamiliar with Linux, or looking for a universal Linux desktop distribution for development, web design, games, and more.
If you're just looking for an operating system that performs both regular tasks and pen testing, you should consider that almost all tools included in Kali can also be compiled or installed on other platforms.
However, if you want to install Kali Linux, there are a few steps that you can take to make it more practical to use regular desktop and Penetration Testing. This can be useful on longer projects, creating documentation or reports, or limiting the number of operating systems and partitions needed on a given system.
The installation of Kali should be familiar to anyone who has ever installed a different Linux distribution. The graphical installer is well run and easy to understand. When installing Kali, there are two special installation steps that you should pay particular attention to. The first of these is the "Setting up users and passwords" page.
The root password for the system can be defined on this page. This is used to manage the installation after it finishes, and it is also used for all commands that require superuser privileges. Keep in mind that this password can be a significant security consideration, so make sure it's strong, but keep in mind that you may need to enter it relatively frequently.