Taping the paper using masking tape before soaking utterly ruins the objective. When wet, the paper swells, but when blow dried, it appears to return to a flat surface. But even with a mild wet wash, the paper bends when you paint on it! You can smooth out any wrinkles with a soft brush or cloth, but they'll come back if you rinse or dry-brush away the paint.
So no, you do not have to tape down your watercolor paper before starting to paint, but be sure to completely blow-dry each piece after washing it in case you want to use it as an abstract painting for wall art.
Prior to painting, many painters soak or stretch their watercolor paper. This is commonly done on lighter-weight watercolor sheets to prevent buckling when wet material is put to the surface. When watercolor is applied, the moisture causes the wet side of the surface to expand somewhat. Without stretching, the paper would buckle under its own weight.
Soaking paper reduces any residual stress in the sheet that could cause it to break when dry. It also helps the paper absorb more paint and hold it better while you work.
There are two types of watercolor papers: acid-free and non-acidic. Non-acidic papers are usually made from wood pulp and are therefore not acid free. Acid-free paper is typically made from cotton or linen fibers and is therefore not susceptible to the effects of acid dyes. Although these types of papers can be soaked, they are not recommended for prolonged exposure to water because the cellulose fibers will rot if exposed to water for an extended period of time.
Acid-free paper is usually specified when you want to preserve the quality of the artwork for later reproduction. If you're going to frame your painting anyway, there's no need to use acid-free paper so you can reuse the frame.
If you don't soak your paper, then once you've finished painting, you need to let it dry completely before moving on to the next stage.
The similar effect may be achieved (though less efficiently) by pasting loose pages to a board with masking tape. Another way is to totally submerge the paper (which should be at least 180 g/m2) in water before painting. As a result, the paper expands consistently in all directions and dries rather flat. This method is useful for large-scale works.
If you choose this technique, first cover the entire surface of your painting with a thin layer of water. Let it sit for a few minutes until it's almost dry, then remove the paper. You should now be able to lift it up without any wrinkles. If not, repeat the process until all the water has been removed.
A third option is to use spray adhesive instead of water to secure the paper to the board. This has the advantage of being fast acting and waterproof once dry. It also allows more freedom in how you position the page compared to tape which limits where you can place it.
Finally, you can use rice or sand as weighting agents to flatten out paper paintings. This is useful for larger pieces when using a lot of white space on the paper.
All these methods will work fine for most types of watercolor paper. Just make sure that the paper you use is strong enough to take the extra weight imposed upon it.
If you're going to watercolor, you must use proper watercolor paper. A watercolor wash on standard copy paper and another on watercolor paper with the identical paint mix are shown below. Because copy paper is not created in the same way as watercolor paper, the wash is buckled and wavy. The ink on the paper prevents the water from spreading and creates a ripply effect when dry.
The best place to find out if you can watercolor is with some samples of your proposed media. There are several places where you can order samples. Most art stores carry a variety of brands of watercolor paper for you to try out. If you do a search online, you should be able to find some companies that will ship samples directly to you.
You should also ask yourself why you want to watercolor on copy paper. There are many reasons why this might be desirable. For example, if you plan to scan your work for digital posting, you will need a smooth surface. The texture of copy paper would just make it harder to read what you were scanning!
Finally, remember that you can always add more paint later. If you apply too much water at first, you can always come back and touch up your painting after it's dry. You can't do this with copy paper - it's gone once you tear it off the roll.
Check out these basic guidelines for drying damp paper: Microwave the paper for about 15 seconds to allow some of the water to evaporate. After that, use a heavy instrument to press the paper flat to remove creases. If you have a book or binder full of damp paper, lay a paper towel between every ten pages to absorb moisture. The paper will be ready when it's completely dry.
The best way to dry paper is with a heat source such as a hair drier, oven, or stove burner. This will remove most of the water from the paper fiber. Be careful not to burn your paper though; heat can cause damage to the fibers of your document. If you choose to use a heat source, turn the temperature down low and be sure to leave it on for several minutes after you think all the water has dried.
If you don't have access to a heat source, like if you're camping or something, then use your imagination! You could use the sun (but make sure to protect yourself from its rays) or even use a fan to help speed up the process. Just make sure you don't use a fan in direct contact with the paper; they can blow away any positive ions that may be present on the paper surface and thus destroy its print quality.
Finally, if you're still looking for ways to dry your paper after all these options have been exhausted, there is one last thing you can do: wait.