sorry for trip post >___<
Okay, it didn't make sence -.-''
On the top bar, you have two squares, a black one and a white one.
The one that is at the top of the two of them, is for your brush colour.
the one at the bottem of the [white one] is your background colour.
Click on the squares to open the mini colour chart,
In the top right corner you have a small Picture, when you click on this, you will get a more advanced colour grid.
For the tools + other features just explore with them, Once you've got the hang of it, it should be easy ^^