Working with just what you have, I like the burlap liner on the outside where you can see it, and the cardboard liner on the inside where you can’t, with drainage holes, of course.
My favorite ‘finds’ are old metal kitchen items - flour sifters, colanders, etc. to line and fill with dirt and Pansies or herbs. I think it looks so cute!
Last year at the township dump, I got an antique wagon wheel planter, gorgeous worn white paint, one welded-on large pot holder on the left and right side of the wheel, and welded feet to keep it upright.......and 2 wire hanging baskets, and 2 matching railing-attached metal planters (only needed liners). Also got 60 assorted clay pots! Clay is my favorite because my grandparents grew things in them at their glass greenhouse/garden center/floral shop way back before commercial places used plastic. Clay is so charming. 🥰