Focusing on a task (such as relaxing and breathing through a contraction) will help reduce your perception of pain. Another way to think about focusing is to use the idea of being "present in the moment." What this means is that you're totally focused on what you're doing right now. You can practice this skill by focusing on a single thought, object or sound. Start by trying to maintain your focus without having your mind wander for just a few seconds in a quiet place. When you can do it for a few seconds, increase it to 30 seconds and then to one to two minutes. Then move to a more noisy area to practice.
Your breathing pace and style are closely linked to your sense of calm and ability to relax and cope. If you find that you're caught up in pain and tension, the quickest and most effective way to break that cycle is by taking one or two cleansing breaths (a deep breath in and out). There are a variety of breathing styles, and yours will probably vary. The first task is to figure out what your normal pace of breathing is when you're doing something quiet (but not sleeping). Have someone check you several different times, and then average the number of breaths in order to find out your normal breathing pace during pregnancy.
A cleansing breath is used at the beginning of a contraction to help you get started in a relaxed, focused way. Likewise, each contraction ends with a cleansing breath to remind you to relax after the contraction has ended. Think of the beginning cleansing breath as a welcome to each contraction because it's bringing you closer to meeting your baby and the ending one as a goodbye to a contraction.
When you're breathing to maintain relaxation, you'll probably breathe at about half your normal pace. This is slow-paced breathing, which supports your efforts to relax and is calming. If you find yourself becoming bored, you can make it more specific by intentionally breathing in through your nose and blowing out through your mouth. This causes your brain to pay more attention. You can also combine it with movement (such as walking, swaying or rocking), vocalization (soft moaning, singing, humming or a mantra) or imagery (such as visualizing a wave rising and falling as you breathe).
If you find you need something more focused, you might breathe at a faster rate, not to exceed twice your normal rate. This is modified-paced breathing. Breathing faster gives your brain a more specific stimulus; since your brain likes novelty, it will pay more attention to a change. This pace also causes you to be more alert. The downside is that it causes you to breathe a little less deeply and can be tiring. As you breathe a little faster you might tend to use your mouth rather than your nose to breathe in. Do whatever is most comfortable.