In a one-story house, the antennas of the WiFi router usually need to point straight up and down, since the wireless signal is broadcast directly to the antenna. Placing the antennas horizontally is not very useful for single legend situations because there is no need to expose up and down.
In a multi-story building, users should point the antennas of the WiFi router straight and square. This ensures coverage below where the WiFi router is located, as well as below and above the router. Most modern routers come with at least two antennas, but if your router has one, direct the signal to where WiFi is most needed.
In most cases, for devices with multiple antennas, it is wise to point the antennas in different directions to cover as much of your home as possible. Most routers now come with four or more antennas, which means it’s possible to position the antennas vertically, horizontally, and at 45-degree angles to spread coverage around your home.