You will find that extremely busy papers do not look good under the transparency papers. Neither do papers with extremely large print or line art, as they are often too big to be able to distinguish it as anything other than a blob of colour.
Select small text or script, perhaps a map if it is not too busy or a small tone-on-tone print. Move the transparency around until you are happy with the pattern that shows through.
If you find a paper that you truly love, but it is still too busy, there are a couple of tricks you can use. Tear a small piece or two of light coloured tissue papers or mulberry paper & lay this under the areas of the transparency that need lightening up; perhaps behing the face & hands, for example.
You might also try a small amount of acrylic paint or glaze in some of the open areas.
Artist: Cheryl Husmann