The smaller the angle between the directional motion of a droplet (downwards, with some slight horizontal component) and a surface it comes into contact with, the less force is imparted on the droplet when it comes into contact with that surface
The slower the droplet, the less force imparted on the droplet when it strikes a surface. In practical terms this means that nearer surfaces (less time for the droplets to accelerate due to gravity) cause less of a splash when struck, and if the pee stream hasn't separated into droplets but is instead a cohesive stream splashing is further reduced
It's a natural consequence of putting extra effort into pushing a pee out, that tiny droplets are going to leave the stream at source and fall independently of the main stream, with a greater sideways speed - aiming towards the middle of the bowl will ensure these stray droplets have a better chance of ending up in the bowl, as will moving source and destination closer together
So we're looking for a way to arrange the lowest force possible, as higher forces break droplets up more and cause more splashing over a wider distance
The absolute best way to minimise splashing is to sit down and direct the stream towards the centre of the bowl. It matters considerably less where the stream goes when sat as it doesn't have as far to fall so accelerates less due to gravity, is more likely to still be a cohesive stream when it comes into contact, and is more likely to catch nearly all the tiny stray side drops leaving the main stream at source
I presume however that you're talking about standing up
Most toilet bowl walls start out steep near the rim then flatten out as you approach the water, before dropping to a steep wall again for a few inches above the water. They're like this at the sides and front but are generally a single steep wall down the rear part of the bowl. Yours seems (it's a bit hard to make out the bowl shape in your image) to follow this rule but the rear wall is less pronounced. The best place to aim for for minimal droplet splash is the steep parts near to the water; they're central to give the best chance of catch tiny side spray droplets, and they're vertical to help falling droplets hit the surface and experience a low force/not smash up.
Because of the reduced size at the front and the sides, consider aiming for the back wall, a few inches above the water as this location is most tolerant of misses/wandering, unlike the sides and front where if you miss the droplets instead strike the most horizontal part of the bowl, the location where greatest smash-and-splash occurs.
If your toilet has better steep walls at the sides rather than the front or back, consider changing where you stand to make it easier to leverage the steeper part of the bowl (the stream travels away from you as it falls, so it's easier to hit a steep section if you're facing it rather than being side-on to it)
By striking a few inches above the water, friction will slow the stream down and before it enters the water, reducing splashing from the interaction between water and stream. It also has the added bonus of being relatively silent, if you have light sleeping inhabitants of the house
Aim for the steepest part of the bowl near the water, that's easiest to hit/offers the biggest surface to tolerate wandering. In the following image this would be to aim for the green dot, and you have the entire panel within the blue dots to cope with wandering. The pink dots at the sides and front would also work and are "better" because they're steeper but "worse" because they are harder to hit. If your aim is really good and really consistent go for pink, otherwise green is a better compromise between steepness and ease