Installation is simple, all you have to do is specify your music library (you can add other later if you want). Mixxx will then import your collection, which may take a few minutes if you have lots of files, but it will only do this once.
Mixxx's interface might be a bit intimidating for beginners, but if you're eager to learn, it's not difficult to get the hang of it. There are two channels, and you load tracks into them with a right click. Each channel has its own controls, from play and pause to tone control. In the center are the global controls, with volume, balance and most importantly the cross-fader which allows you to mix between the two channels.
Mixxx is controlled either with the mouse or hot keys, which are specified in the included manual. In terms of help for beginners, each channel has a "sync" button, which will attempt to synchronize the BPM (beats per minute) of one track with another. The user still has to start the track in time with the other one, so Mixxx won't do the mixing for you!
Mixxx is a solid DJing application, with good BPM estimation, and controls that are easy to pick up for anyone who's seen a mixer before, and intuitive enough for a beginner to learn.
Download Mixxx 1.8.2 in Softonic