Summarize:

If you’re altering a preexisting image to make your GIF, make a copy of the file first. Editing images may cause irreversible changes. So, be sure to save the original picture before editing it. Paint is a program that can be used to make original drawings on a blank page or on top of other images. Paint can be used to make a GIF, which is short for Graphic Interchange Format—a small 8 bit (or 256-color) image format which is relatively fast to download on the net. The toolbar includes a number of basic and familiar tools, such as erase, magnifier, and pencil. It also has select, free-form select, color pick, and color fill. Free-form select designates irregularly-shaped objects in your picture, and pick color helps you set a foreground or background color based on the color you pick. Paint also includes brushes of various styles, lines of various thickness, a large collection of shapes, background transparency options, and a full color palette. You can customize colors or pick a specific color using the color pick tool. Size options can be very helpful. In Paint versions after Windows XP, you can resize images after drawing them. To enlarge and image or to view the screen in more detail, you can also use the magnifier or full-screen viewing option.
Copy first. Learn the basics of Microsoft Paint. Familiarize yourself with the toolbar. Use different brushes. Play with different image sizes.