I prefer the mixed stacks because the variations in color make an interesting effect in the blossom. The single-colored blossoms have a bolder color and the 2-colored blossoms have a more subtle effect. Play with the colors and find what you like best.
Stick to stacks of 2 pieces of paper for a more delicate looking blossom.
The blossom on the left was adhered with while glue and the one on the right using a glue dot. We found that the cherry blossoms stuck equally well with either the glue or the glue dot. It’s your preference. You have to wait a little bit for the white glue to dry, so glue dots are better for us impatient crafters.