Take Jungle Formula with at least 50% deet in it. If you have a Home Bargain near by they often have it at the best price. The spray cans are better to use than the liquid, believe me I have tried them all.
Boots own brand really stings, Wilkos/Sainsburys own brand is useless, Avon SSS is also as much use as a chocolate teapot as well as vit B tabs and marmite and eating huge amounts of garlic as well as other old wives tales to rid the little buggers. Citronella in a spray form also IMO does not work, but the candles do help a little.
When you arrive try and either get plug ins or a room spray, which before you go out give the room a good spray close the doors. I would rather do that than suffer with mozzie bites.
I also do find the electric 'zappers' you can buy (Tesco) did work on some bites if you got then quick enough and took a bit of the sting down. But everyone reacts differently to bites.
Take care with clothing if you can covering up when its starting to go into dusk (but in certain areas mozzies etc are around all the time) you can also spry clothing, and watch those ankles, wrists and elbows a favorited place to be bitten
I lived in the tropics (one right next to a large jungle) and in other countrys with mozzie problems and sometimes I still got bit after very careful application, I also tried local sprays/lotions in different countries, the majority of which did not work as they are mainly produced for the local market, and I disagree they work better. One country I lived in all the western ex-pats were bitten to death using local stuff. Nasty nasty dengue carrying mozzies are not nice.