My son is 6 years old and I have been dealing with spillage in the toilet. He himself is very concerned and tries to avoid it by holding his 'thing' and pointing it down. This way he is successful but I am concerned about potential side effects to this practice.
Make note I have always trained him to pee sitting not standing, as it is against my values and also I think it is difficult when you want to wash yourself afterwards with water..
I have also tried making him sit turned the other way. That also minimised the spill but it wasn't 100%.