Caption: An all-sky sky map displaying the equatorial coordinate system, ecliptic, the constellations and the Milky Way.
Features:
Of course, you don't see the stars in daytime usually. They are lost in the diffuse sky radiation (the blue sky) caused sunlight scattering in the Earth's atmosphere.
The convention is probably because in the Northern Hemisphere we usually think of ourselves as facing south when tilting our heads up to view the sky. Viewing the sky this way puts the east on the left-hand side.
We see it like this because the Solar System is embedded Galactic disk about 8 kpc from the Galactic center.
In the Northern Hemisphere, Sagittarius is low in the southern sky in the summer night sky.