The most used tool in Photoshop, and most likely one of the simplest to date is the Paint Brush tool. Your paint brush tool can be found on your toolbar.

Click on your paint brush tool to reveal menu bar at the top of your screen

The menu bar has many options

The first option is the "Mode" The mode of a paint brush are the same as the layer modes, and are used in a very similar way.

 

All of the modes have a different effect, so I can not go over every single one.

Go ahead and select dissolve from the mode menu and hold down the left mouse button and drag your mouse across your image. You should have something like this.

You can play around with all of the painting modes for some real fun :)

 

The next option is the pressure. The pressure tells you how bright your paint brush is going to be, the lower you make the pressure, the less and less you are going to be able to see your paint.

Click on the arrow on the pressure menu to reveal a slider, Move the slider left and right to adjust your pressure

Here is a quick example of the range of pressure you can use with your paint brush

The next, and most exciting option of the paint brush is your "Brush: style. Your brush style is how big or small your brush size will be.

 

Click on the the small arrow to reveal many more sizes of brushes that come with Photoshop

The sizes range from very small to VERY large.

Here is only a few sizes

Not only can you experiment with the brushes that come with Photoshop, but you can make your own! I will cover how to make your own brushes in later to tutorial, so if you want to know how visit the "Defining a Brush" tutorial. Here is a few out of my hundreds of brushes:

You can use them to make all kinds of interesting things!

Well, now you know the basics of using your Paint Brush tool, Visit some more of my tutorial to learn more about the paint brush tool, as well as how to make your own brushes!