Three frequency ranges make up the kick drum sound: the low-end, the mid-range and the high-end. The 50 Hz to 100 Hz range makes up the low-end of the drum. This range gives the characteristic rumbling thud of the bass. The mid-range, from 250 Hz to 1500 Hz, controls the attack of the sound. The high-end, from three kHz to eight kHz, controls the resonance and click of the drum. Apply EQ to increase or decrease these frequencies as needed. Reduce the muddiness of a mix by lowering the 250 Hz band. Increase the presence of the kick by increasing the mid-range and high-end. Experiment with raising and lowering frequencies to find a good sound.
Proper compression of a kick drum tightens the sound and makes it stand out in the mix. Bad compression, however, crushes a kick drum into a lifeless thud. While no universal solution exists, some simple experimentation can help find the right sound. Start with the compression ratio at 6:1, the threshold at -10 dB and the attack at 3.0 ms. Tweak these settings until the kick sits in the mix as desired.
Adding multiple tracks of kick drums can thicken the sound of a weak kick track. Try adding single or multiple kick samples to back up a thin sounding kick drum. EQ the samples, compress them or process them in any way, then mix them with the original. Consider using chorus effects and delay effects to thicken the sound. If it sounds good and fits with the mix, then use it.