Odds are that you're waiting too long before equalizing. Read threads on equalizing and you'll see the same words repeated time and again, "early and often". Most new divers tend to get behind the curve early in their descents, and therefore have a much harder time than necessary.
Ideally you should be equalizing every foot or two at low pressure differentials where methods like swallowing or stretching your neck will do the trick. With 4-8 feet of difference, you'll have to do the Valsalva maneuver or a similar equalizing method. After about 9 feet of depth, the outside pressure will so constrict the eustachian tubes that equalizing is virtually impossible. At this much pressure differential equalizing is like trying to drink a thick shake through a collapsed straw.
If you feel pressure of pain and are trying unsucessfully to equalize, don't force the issue, instead go up close to the last depth where you were equalized, equalize, and resume a controlled descent.
Even if you perfect equalizing technique, you may still have one of those bad ear days. On those days instead of trying to equalize as fast as you descend, you'll have to descend as slow as you equalize.
Unless you're a military diver on a critical mission, no dive is worth risking an ear injury.