Hi, yeah we did this in last weeks anti natal class.
Sit on a chir with your partner behind you with his hnds on your back where your lower ribs are. Take as deep a breath as you can manage through your nose (your parner should feel your ribs expand asyou breath comes from low down in your diaphram) exhale slowly via your mouth, like your gently blowing a candle but not enough to blow it out. repeat this a couple of times. then have you partner move his hand up your back a little to the flats of your shouder blades, this time your inhalation and exhalation should be shorter and come more from your chest so your partner feels your shoulders and back puch backwards, repeat a couple of times again, now have your partner move his hands up to the tops of your shoulders, breaths should be shorter and sharper now and your shoulders should rise with each inhalation and drop when you exhale. repeat a couple of times and then work your way back down through each position again untill your partners hands are on your lower ribs/waist again. Tis whole sequence should last 60/90 seconds i.e the langht of your contraction. Always inhale through your nose and exhale through your mouth. Have you partner use his hands at each stage to remind you to breath correctly as its easy to lock up when you have a contraction and hold your breath or not breath properly. Following this exercise through each contraction should help you to stay calm and relaxed, have your partner say soothing and encouraging words at the same time, or simply count your breathing in and your breathing out to help you concentrate. Your contraction should be peeking when your using your shoulders and ebbing out on the way back down.
Hope that sort of makes sense. If unsure speak to your midwife at your next appointment and she should be able to guide you through it.