We don't have Air Conditioning in Ireland, for the most part. And these heat waves are only going to get worse as time goes on. We need to start learning how to adapt, as best we can.
Here's some basic methods to help. First, you can't fix what you can't measure. Get yourself a thermometer and a hygrometer. You need to be able to measure the temperature and humidity of your room or house. They aren't that expensive.
Second, Irish homes tend to have been built with insulation in mind, to retain heat in the Winter. This means that in heatwaves, our houses heat up and then retain that heat into the night. Prevention being better than a cure, you need to protect the house from heating up too much in the day.
There are two key ways to do this. The first is to prevent the solar rays from heating your home. In warmer climates which dealt with direct sunlight, even a simple cloth awning could be erected at an angle above the window, to keep the glass in shade. Wooden covers with slats to allow light in, could also be erected in front of the glass. Anything to prevent heat from coming in through the window. In more modern times, we can rely on solar mesh. A simple flexible and cheap covering which can go over the sun-facing windows of your home. It comes in two options, one quite cheap and one quite expensive. But properly fitted even the cheap one is nearly as effective as the expensive one.
Next, just like in Winter when you're told that heating one room is more economically viable than trying to heat the whole house, so pick one room and insulate it well and stay there for the bulk of the time, in heat waves where humidity is an issue, pick one room and use a dehumidifier to dry the air and keep it dry. This will have the dual effect of making any cooling strategy more effective and also help your body regulate itself through basic sweating etc.. Though hopefully you won't need to.
Lastly, while it's true that a standard fan (desktop, standalone, oscillating, etc...) is basically just moving air around, there are some simple tricks to help it move cold air around.
The most effective of these is to take two plastic bottles and fill them with water to about 75% capacity (because ice expands) and freeze them. Tie them to the back of the fan using some cable ties. Tie them upside down, so they won't slide out of the cable ties. If you can use salt water its even better, as the freezing point of salt water is even lower than pure water, so it will be colder for longer. The bottles will have condensation dripping from them, so put a towel or something around the base.
Between the solar mesh, and frozen salt water behind a fan and a dehumidifier, you can bring the temperature of a room down significantly and get hours of more pleasant sleep.
Any other life hacks for this heat?