Then apply the next command: Edit – Define Brush Preset to create a brush out of our picture. Get back to the file with the wallpapers and choose a white color and the brush we made up. The brush's size should be changed when adding the bubbles to the ornaments we already have:

Designing Marine Wallpaper

Select the Dodge Tool to decolorize the ornaments' edges:

Designing Marine Wallpaper

Merge down all the layers: Layer – Merge Visible (shift+ctrl+e). We have to dark out a little the wallpapers edge in a way to accentuate only the middle of the picture. Copy the new layer
and make the corrections on its brightness and contrast: Image – Adjustments – Brightness/Contrast:

Designing Marine Wallpaper

Create out of this layer a mask: Layer – Add Layer Mask – Hide All and choose the Gradient Tool of white color to make the layer visible only along its edges:

Designing Marine Wallpaper

Combine the layers (ctrl+e) and the last step includes erasing the black color from the picture, using the next combination: Image – Adjustments – Selective Color.

Designing Marine Wallpaper