I have been using CyanogenMod ROM on my phone since the starting and the ROM is very quick. The reason why most people end up installing CM on their phones is that it gives you the Google experience with enhanced features and customizations ability.
What I like the most about CM is that you can change the System UI by applying themes on your CyanogenMod. Apart from that, you can also use apps which need rooted phones and you can also extend the functionality of your phone by using other MODs like Icon Themer.
The developers over at Cyanogen released a new app, CyanogenMod Installer which makes it easy for everyone to install CM ROM on their Android phones. The app is currently available for Windows Vista, Windows 7 and Windows 8 only and OS X app will be available soon.
They also released a companion app for Android on Google Play Store to guide the users through the process. The app is currently in beta and supports a limited number of phones, includes mostly the flagship devices but it will soon cover more devices.
You don't have to be rooted phone to use the app, the app doesn't cares if your phone is rooted or not but you need to be running on Stock ROM. Also, you don't have to have unlocked boot loader. If you're already on a Custom ROM and want to use the app, you can unless it recognizes your phone. The app should recognize the supported phones.
How to Use the Installer
Install the CyanogenMod Installer on your desktop and install the companion app on your phone. Now, run the Companion app on your phone and follow the on-screen guide. Since the app is currently in beta, it supports HTC One, Nexus 4, Samsung Galaxy S2, S3, S4, Note, Note 2, Nexus 7, 10 and Nexus S.
You will end up with a bricked device if you try the app on a phone that's not listed in supported device.
Since the app currently doesn't includes the system backup option, you should backup your system before getting started so that you can flash it if something goes wrong.
Download(Android App, Desktop App)