Download or purchase a Virtual Studio Instrument (VST) Sampler from a retailer and install as per instructions from distributor. A VST is software that mimics the functions or sounds of hardware instruments. Freeware and retailer software samplers are available as stand-alone programs and most music composition software integrates a software sampler.
Power down your PC and connect your MIDI device. Most modern MIDI controllers are USB compatible; however, some units require an intermediary MIDI to USB device. MIDI to USB devices are available from most commercial and Internet music retailers. USB MIDI devices are generally plug and play whereas a MIDI-to-USB converter may require drives which are included with the device or install automatically.
Load your VST sampler either by running the stand-alone software from your programs menu or applying the VST sampler to a track in your music recording software.
Select a cell on your software sampler and right click to apply the waveform you wish to play. Software samplers either offer a browse function or draw waveforms from a preset path. If needed, set the path to the folder the wave forms you wish to play are stored, usually a function under the software sampler's options or preferences menu.
Set the range of the cell to the key or keys on your MIDI controller you wish to correspond to the wave file you selected. The key range denotes the note letter and octave of your MIDI controller. For example, C4 is standard for middle C in MIDI. If you want the wave file to play on only one key of your keyboard, set the lower and upper bounds of the key range to the same value.