You will need to monitor the direction and angle of approach to gauge where to aim. You will also need to take into consideration doppler effect on approach and depart, as this will change the frequency up and down. You will likely need to aim your directional antenna (assuming you're using one) this way and that way until you get the sat too. Tuning into a beacon freq is usually easiest as that is typically always broadcasting in sunlight. Otherwise, if you're looking for packet transmissions and voice you may or may not hear something when aiming right at the sat. Good luck.
You first need to find out the orbital location of the satellites you want to receive. I'm familiar with the US orbital slots but not EU. Since you are north of the equator all the geosynchronous satellites will be somewhere between east and west and all will be south to some degree.
Once you find the orbital slots you want to listen, go here then enter your location and the orbital slot and it will give you azimuth aiming instructions in true or magnetic north and an elevation to point. Satellite Finder / Dish Alignment Calculator with Google Maps | DishPointer.com This site will also draw a line from your location to the satellite, so if you drag and drop the starting point to your house it will show you if any trees or tall buildings are in the way.