Health: The Rock is encouraging us to brush up on baby first aid, here's what you need to know

As well as being a Hollywood actor, producer, fully-fledged Instagram star – oh, and there are rumours of him running for US President in 2020 – Dwayne 'The Rock' Johnson has found time in his busy schedule to brush up on his baby CPR skills.

The 45-year-old Baywatch star, who is expecting his second daughter with girlfriend Lauren Hashian this spring, took to Instagram to post an important message about parent safety to his 100 million followers.

"You hope there's never an emergency where you never have to deploy the skill," Johnson wrote. "Since we have another baby girl on the way - I wanted to make sure myself, my family, and our staff took another choking prevention and CPR course on infants, children and adults." He recommended learning CPR to his fans because you "never know what may happen and it's always best to be ready".

So what exactly is baby first aid and how do you do it?

CPR stands for cardiopulmonary resuscitation. It's a life-saving medical procedure which is given to someone who is in cardiac arrest. In the event of an emergency, it helps to pump blood around the baby's body when their heart can't. To carry out CPR, a person presses up and down on the casualty's chest (chest compressions) and gives them a series of rescue breaths to help save their life.

Many new parents worry about their baby not breathing from incidents such as drowning at bath time or stopping breathing in the night. The Red Cross has four-hour baby first aid courses available regularly in around 50 UK venues, but if you can't attend a local session, there are plenty of important pointers you can pick up at home.

St. John Ambulance has advice on administering CPR to your baby, recommending that all parents learn the first aid skill in the event of an emergency where your baby is unresponsive and not breathing.

"If your baby is not responding to you, try to see if they react when you gently tap or flick the sole of their foot," says a spokesman. "If they are unresponsive and not breathing normally, open their airway and check their breathing again by looking for chest movement, listening for the sounds of normal breathing and seeing if you can feel their breath on your cheek."

If you can't feel your baby's breath, you need to call 999 and start CPR straight away. If you're on your own, experts advise you give one minute's worth of CPR before you call for help.

To give rescue breaths to a baby, first check if there is anything in their mouth, pick it out and ensure the airway is clear and open.Take a breath in and place your lips around the baby's mouth and nose to form an airtight seal.If you cannot make a seal around the mouth and nose, close the baby's mouth and make a seal around the nose only.Blow steadily into the mouth until the chest rises. Remove your mouth and allow the chest to fall. Repeat four times more. Now give 30 chest compressions.

How to give chest compression to a baby

Place two fingertips of your lower hand on the centre of the baby's chest.Press down vertically on the breastbone, and press the chest down by at least one-third of its depth. Release the pressure without moving your fingers from their chest. Allow the chest to come back up fully - this is one compression. Repeat this 30 times, at a rate of about twice a second - the speed of the song 'Staying Alive'. Now give two rescue breaths. Carry on giving 30 chest compressions followed by two rescue breaths for as long as you can, or until help arrives.

Getting into the recovery position

If the baby starts breathing normally again, stop CPR and put them in the recovery position. To do this, cradle them in your arms, with their head tilted downwards. This will keep their airway open and stop them choking on their tongue or breathing in any vomit. It's important to continue holding the baby in the recovery position until help arrives.

Experts say doing CPR right away can double or even triple a baby's chance of surviving cardiac arrest, so it's well worth taking The Rock's advice and memorising these key steps so you know how to act in a life-threatening emergency.