Purchase the appropriate audio software if you don't already own it. There is a plethora of audio creation software available online and in brick and mortar stores. You want to purchase one which will allow you to import your own audio and also add your own musical instrument effects. It is also important that you are able to change the beats per minute (BPM) of the track, as this will create the tempo you want.
Import a track to go 'under' your krump beats. It should be a track with energy, and a fast rythym--something approaching 140BPM would be preferable, although you can edit that in your software. You should also make sure it has something of a repetitive quality to it, because it is your own customizations which will give the track its character. For good examples of krump beats and audio representation of how often the beat should repeat and the tone of a good track it would be valuable to visit the Experience Music, Song Area and HXC Music websites.
Change the BPM to around 140 if it isn't already. This gives you the appropriate speed for this type of music, and the associated dancing.
Insert your own instrumental effects. Most common to this brand of music are bass lines, snares and claps; all of which will give your track a krump vibe. Use your own discretion and experimentation to decipher the correct time to slot these effects in.
Experiment until you are happy. There is no sure-fire way to create a krump track; it is a case of 'practice makes perfect' and keep mixing things up until you are happy with your mix of all the creative aspects.