If you want to do comic book restoration, you should experiment on any old book first. This is so that if you ruin the book, you will not have any money lost and you won't have destroyed a comic that may have a high value among collectors. Restoration is a fine art that attempts to restore the comic to look as much like the original copy when it was first published as possible. However, restoration does not add to the value of the comic book and often diminishes the value significantly unless it is sold as a restored comic that someone wants simply to complete a collection.
Some of the techniques that are often used in comic book restoration include reglossing. This is a technique where a silicone or a clear spray is applied to the cover of the comic to make it look glossy and appear to be in a lot better shape than it really is. Some collectors view this technique as being unethical and it actually reduces the value of the comic instead of increasing it.
Small tears are often repaired using rice paper. The pastes that are used are similar to paste used for wallpaper, but is much finer. It is really hard to detect rice paper on a comic book, but if you look closely you will see that there is a dull sheen that does not reflect the light in the same way as the rest of the page. Another way that tears can be repaired is to use heat seal paper. This is also a form of rice paper, but it is coated on one side with a heat-activated glue. Using a proper heat seal iron, you glide over the paper and seal it. This too leaves a dull sheen that is often difficult to detect.