Starry night background.
1. Get a dark dark shade of purple or blue, and fill an empty layer with it. Make sure that the empty layer is last.
2. Take a dark green colour, and make the ground. I made it curved to look more natural, like a hill.
3. Get a very light yellow colour and make a circle, take the background color and make the moon a crescent shape.
3. Take white, and make sure the width of the brush is 0, make dots all over.
4. Take a lighter version of the sky colour, and make dots all over.

Simple Background with shadow.
1. Fill an empty layer with a colour of your choice.
2. Pick a colour and go around the edges with that colour to make a border.
3. Use that same colour you use for the border to make some patterns.
4. Pick a colour for the shadow and go around the outline of the character.
5. I do this all on the same layer.