I had to do this one after i found slide mailers at a bargain price and made people buy them lol.
I found a lot of old postage stamps i forgot i had and as i have some postal themed stamps, i just had to do a postal theme for these.
I used a burgandy acrylic paint with a drop of metallic paint added to paint both mailers.
I then stamped with stazon added stamps then on the front of both i used crackle glaze but i must have been stingy as you could see the brush strokes and i wasn't happy with the result so i then put on anitas 3d gloss but i used a paintbrush and did what you shouldn't lol. I applied it in a circular motion adding lots of air so it was very bubbly then when dry i sanded it back and i have a lovely aged effect which i used on the inside as well. I think you will be seeing this a lot more in my work.