Border- overlay as many different snowflakes as the vertical space could hold. To create depth, use different shadow opacities

Background: Place a solid paper over a patterned paper - reduce the opacity to just see the pattern below.

Add extra texture,- place a gesso page overlay on top of the solid paper and use it to cut out parts of the solid paper then delete the gesso leaving behind the gesso pattern cut out of the solid paper

Do the same technique with the photo. to make a mask.