Purchase an appropriate laptop. Selecting a laptop for DJ use does not have to be a difficult process. The laptop can operate on the Apple or PC platform, with most DJ software available in both formats. Audio applications require a fast processor with plenty of RAM to provide high-quality output. You also need a large hard drive to store your music collection. Tweak your computer by removing or disabling programs and applications that you do not want running during a performance. Consider deactivating all audio prompts to avoid blasting a Windows prompt through the club speakers when you attempt to close an application on the laptop.
Invest in a high-quality external sound card. The sound card included with most computers is intended for home use, with most sounds amplified through computer speakers. When a laptop is connected to a club system, the sound card often produces a fuzzy or diminished sound. Avoid this by purchasing a high-quality external sound card from a DJ equipment store. Most external cards come with software that helps you install the hardware to operate with your laptop's operating system.
Research DJ software packages. A number of software packages on the market are designed to help DJs perform music live at a club. These packages go far beyond the basic mixing of two tracks, offering the functionality to add special effects, looping, sampling and syncing recorded sound with live instruments. Two of the leading packages are Ableton Live and Traktor and are used by some of the world's biggest DJs. Many DJ packages allow prospective buyers to download a trial version of the software free, letting you experiment before you invest.
Purchase a Midi-capable control device. Using a computer to DJ a set can produce a high-quality musical score, but is fairly boring to watch. To compensate, most DJs choose to use a control surface that avoids using a mouse to operate the software. These surfaces can be easily programmed to permit the DJ to load songs, apply effects and create loops on the fly, all by pressing buttons and turning knobs on the controller.
Build a song library. To use a laptop effectively, a DJ needs a library of high-quality digital song files. These files need to be saved in a format that can be read by your DJ software package, with MP3 and WAV files the most common formats. It is essential for MP3 files to be recorded with a bit rate of at least 192. Songs recorded lower than this bit rate will sound muddy and distorted when performed through a club sound system.