With this in mind it was perhaps unwise for my diving instructor in Egypt to give my sister - and dive buddy - an underwater camera, just minutes before our first serious dive.
As she experimented with the settings, I saw my safety disappear in a cloud of fish pictures. Having spent two days learning to scuba dive among the colourful coral reefs of the Gulf of Aqaba, off the coast of northern Egypt, our dive master John had decided we were now ready for a deep dive.
"This dive site is called the Blue Hole," he explains. "There's nothing to worry about - although the start involves going upside down through a tunnel".
Camera in hand, my sister quickly submerged with the air of an expectant Japanese tourist.
Wishing myself back to our five-star hotel Le Meridien Dahab - I took a deep breath. Then remember I'm not supposed to do that.
. Sarah O'Meara Meridien Dahab with Tropical which offers breaks On the way down I comfort myself that, if I drown, my sister will definitely catch the moment on camera. ex-Manchester, taxes and 9605 or adiving.
For newcomers, the initial stages of learning to dive can test your nerves and patience.
Your first day will most likely be spent kneeling underwater in a cold swimming pool, wearing fins and strapped to an oxygen tank.
As you are repeatedly asked to fill your face mask with water, forced to remove your oxygen supply, and told off for crashing while attempting not to shoot to the surface of the pool, you may find yourself questioning your choice of holiday activity.
Just metres away on dry land the other guests are being served cocktails by the waiters and revelling in a delightfully temperate climate.
I'd made it through those testing times, and as I watched my sister gracefully appear from under a rocky arch into a shoal of yellow fish, my breathing returned to normal.
The worst over, our dive master took us on a tour of the coral, and I followed, trying hard not to send up clouds of dirt or destroy the delicate reefs. Pointing out various different fish, he keeps making a strange hand signal which I eventually realise means "sea turtle". Spotting one of these prehistoric creatures (which first appeared about 65 million years ago) is an unworldly experience, and as I watched my sister scare it with her camera, I realised just how lucky I was to be there.
Our group of three stop to stare into dark holes, where lugubrious, Disneystyle fish peered out of the gloom, before swimming through tiny clouds of bright blue swimmers.
The coral tabletops in this part of Egypt are healthy, in beautiful condition and home to a wide range of fish, including a fish called cleaner wrasses that swim into your mouth, or rather the mouth of our "fun-loving" dive master.
With no more effort than you'd exert in a gentle Pilates session, we glide past these glorious sights, lucky to be in a small group with a dedicated guide.
Not far behind are large groups of divers from the town of Sharm El Sheikh, who crowd into the small dive sites of the Red Sea with irritating regularity.
TRAVEL INFORMATION Sharm is attractive to those looking for affordable diving holidays, but their diving package comes at a price.
travelled to Le Resort in Egypt Sky Scuba Diving seven nights' halfboard from pounds 788 in June, inc transfers, surcharges (0870 907 holidays4scub co.uk) The more people there are on a dive trip, the longer everything takes to set up, and the less intimate your dive will feel.
We are lucky to be staying at a hotel that's avoided all pressures to join the all-inclusive bandwagon.
Poseidon Divers takes care to avoid the crowds and, where possible, heads towards sites such as the Ras Mohammed National Park, where other visitors seem to be marine biologists.
Le Meridien Dahab is on the outskirts of the former Bedouin village of Dahab, 40 miles from Sharm El Sheikh.
Dominated by a long strip of shops, bars and restaurants, there's still no way to avoid the "hard sell" typical of Egypt, but the overall atmosphere of the town is hippy rather than commercial.
Bedouin-style cafe and bars, where you sit on floor cushions sipping a drink and looking out to sea, are hard to beat after a day in the sea.
Situated on a long curve of land overlooking the sea away from the town, the large complex boasts a Padi National Geographic Dive Centre, windsurf centre, kids club, fitness centre, tennis courts, three restaurants, five pools, a spa, as well as a beautiful beach which is a great place to switch off from the outside world.
to regularity. Sharm those TRAVEL INFORMATION . Sarah O'Meara travelled to Le Meridien Dahab Resort in Egypt with Tropical Sky Scuba Diving which offers seven nights' halfboard breaks from pounds 788 in June, ex-Manchester, inc transfers, taxes and surcharges (0870 907 9605 or holidays4scub adiving.co.uk) the
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