Wrought iron is a misunderstood term. Modern wrought iron is made from 1018 mild steel rather than the low-to-no-carbon iron of the past, due to cost. "Wrought" means worked by hand. The methods used to produce the rails, supports and scrollwork seen in true wrought iron take time and practice to perfect.
Design your wrought iron to fit and complement the space where you intend to install it. Choose small projects first, until you perfect your techniques. Make individual wrought iron design elements, such as "S" hooks, curls and scrolls to practice heating and bending iron to shape.
Use the mural transfer images at the Wall Dressed Up website to choose which elements you want to use in your design. Use an overhead projector or graph paper to enlarge the design elements to the size you need.
Heat one end of a scrap steel rod or bar to bright orange, as seen in dull light. Use vise grips to twist one end at a time to your chosen shape. Reheat the other end of the rod and repeat. Make as many of each design element as you have pieces of scrap steel available. Repeat for bar stock scraps.
Take the best of your practice pieces and lay them on a workbench or floor in your chosen design.
Measure your doorway and your chosen design, to be certain that you will be able to take your finished piece out of the shop. Adjust measurements or move outside before permanently joining any parts.
Don your welding helmet and full leathers and have a large, fully charged ABC fire extinguisher within hand's reach. Weld all pieces of your design where they touch, until you have attached all pieces to one another. Grind all welds smooth using your choice of hand-held grinder, 24 and 80-grit wheels.
Work slow and small, and be patient with yourself. Blacksmiths and ornamental ironworkers spend 20 to 30 years perfecting their techniques. Your first few pieces may be crude and fall apart, but you have to begin somewhere.