I go to Caribbean very regularly. Jungle formula works for me - but not the spray, the roll on is more effective. I buy from Savers it's £2 or thereabouts.
I never forget to use the roll on whilst there, I carry it out with me so I can top up every few hours. Definitely has to go on when that dusk chorus starts. But you can get bitten both day and night.
Also use Avon Skin So Soft, the one in the green bottle.
If you're in a high mosquito area then a stand up oscillating fan in your room - it blows them about, they don't like it.
You can buy an electric insect killer to plug in and leave in your room.
People do use Bop or Off spray. Mainly for spraying your room and then shutting the door before heading out for the day. Not for when you're sitting indoors.
I've never known citronella to work.
You can buy mosquito coils if you can stand the smoke.
Daily antihistamine tablet in case you get bitten as it helps with itching, and stopping the bite from raising.
Trousers and loose fitting long sleeved top for evenings makes sense. If like me you don't always want to wear that then you just have to be vigilant about repellent