Here is the next "beginner's tip".

Although I do not really know if I can really call this beginner's tip, this also helps those who are more than beginners! :)

What colors can be combined with each other?

Answer: Everyone !! But some colors are lighter than others. If you want to shade two eye shadows in different colors, it is easiest to choose two colors next to each other in the color circle!

The famous color circle. 

Colors that most easily go together are thus as logical as the following:
Green + yellow
Yellow + orange
Orange + RED
RED + pink
Pink + lila
Purple + blue
Blue + Green

Shows some examples!

Green – yellow

Yellow – Orange

RED – Pink

Pink – lila

Purple – Blue

Blue – Green

As you can see in many of the pictures, you can easily use this even if you want to use more than two colors in the same make-up! Then you easily take colors that lie consecutive in the color circle:

Yellow – Green – Blue
Blue – Purple – Pink
Yellow – Orange – RED

Yellow – Green – blue – lila – pink

etc

Hope this was helpful!