Hello there. This tutorial is meant if the only program you have is MS paint, well here's a short guide/tutorial to get you started ^^
The Tools

1. Free-Form Select. This tool allows you to cut out an image not in a perfect square. This comes quite in handy when you're trying to cut something out of an image in a certain shape.

2. Select For this tool you can cut out an image in a perfect square, the free-form select will be a lot easier to use if you need to cut out a certain shape.

3. Eraser This is the most useful tool there is, the eraser. It allows you to erase mistakes you make, select the size.

Smallest to largest, smallest comes in handy when you make a small mistake, largest comes in handy when you make a big mistake and have to erase it.

4. Fill Let's say you're colouring in a picture? Don't want to take a lot of time colouring in, well just use fill. It's really easy to fast-colour in the smallest spaces.
5. Eyedropper If you want to make a font, or layout and want the colours to match, use this eyedorpper tool to select the exact same colour.

6. Magnify This tool comes quite usefull when your drawing a small picture, click it and magnify the spot you wish to draw - easy! Just remember to draw big, or when you un-magnify it it'll probably be really small

7. Pencil Ahh, the pencil. Quite simple to use, simply click it and draw.

8. Paint Brush This tool is much like the pencil, except you can choose if the brush is square, round, dashes ect.

9. Spray Can There's not much to say about this tool, it's simply like the paint brush except in a differant form. Use this if you want the "spray can" technique.

10. Text This tool comes quite in handy when you want to write something down, instead of using the paint brush or pencil to do this. This tool makes it very neat.

11. Line Want a straight line? Then use this! Haha, that sounded like a comercial. Anywaays this tool you can make a straight line and choose the thickness of it.

Curved Line Use this if you want a curvy line, there is not much to say about this tool.

Shapes If you want a certain shape, but can't draw it free-hand, use this. There is also a little trick which I like to call "multiplying image" You draw a circle, then select it hold shift and drag it around. This is what it'll end up like:

Make sure the setting is transparent though, or it won't work.

MORE TRICKS : COMING SOON!
~Lolly