Drink loads of Bottled water (make sure you to check the seal on the bottle before buying it). Buy a box of 10 sachets Rehydran salts from the pharmacy in Sharm for 2LE and dissolve them in some water. This will help prevent dehydration.visualcage.ru
Have and use sunglasses, maybe a spare pair in case you lose them.
Creepy crawlies are a fact of life in a hot climate, mainly coakroaches. The hotels try very hard to prevent them but to get them all is impossible. If you spot them please tell the hotel staff but do not create to much of a fuss.
Mosquitoes are around in Sharm, but it is not a maleria area. The number of them is not high and they tend to appear in seasonal cycles, mainly in the cooler months. If you react to their stings then I would suggest a net to sleep under and use a repellant in the evening
Pack a basic First Aid kit with you. Include pain killers, plasters, antiseptic, Imodium
Make sure you have suitable medical insurance – a lot of travel insurances do not cover diving. So check the small print as some of them only cover you to 9m.
Remember that Arabic is the language. A lot of Egyptians who do not regularly come into contact with foreigners only speak this language so patience is required to make people understand when you are not speaking their language. Generally they are a very friendly race and will try and help.
A good way to get on, if somebody does not speak your language, is to make jokes that are very obvious and simple to understand. This shows that you are not angry or serious.