How to Soak Stamps
After you cut or tear the stamps off an envelope, you will have to soak them to get the backing paper off the stamp. Do not try to tear this envelope paper from the stamp since you may damage the stamp. Torn or damaged stamps are worth nothing and are not considered a collectible by stamp collectors.
First, trim the envelope paper close to the stamp, but take care not to damage the stamp or the perforated edges. Now comes the soaking section.
Use a shallow bowl, or a kitchen sink with the drain closed and fill it with several inches of lukewarm tap water. Do not use hot water, since it may make the color run from the stamp.
Float the stamp picture side up so that the gummed side is below the water level. Don't soak too many stamps at one time since they may stick to each other with the glue that is still left on the stamp.
Let the stamp float until the stamp slide easily off the backing paper. Remember that paper, when wet, makes it very weak and it is easy to tear the stamp. So, let the water do the work in getting the stamp off the paper backing.
Rinse the stamps gently in fresh water to make sure all the glue and backing paper is off the stamp.
If you are soaking a lot of stamps, you may want to change the soaking container to make certain the water is clean.
Place the stamps to dry on paper towels or newspapers. Put the with the picture side down so that if any glue remains on the stamp, it doesn't adhere to the drying paper. Also, don't use colored newspaper pages since the color from the comics may transfer to the stamps. Put the stamps in a single layer so that they don't touch each other.
Wait until the stamp are completely dry. They may curl or look wrinkled, but that will be taken care of in the next process.
Once dry, put the stamps in a telephone book or any other book, and leave them there for a day or so. When you take them out, they will be nice and flat.
Self-adhesive or self-stick stamps may present a problem in soaking. It may take a while longer for them to separate from their backing paper. But be patient, the paper will come off the stamp.