I cannot show you a portfolio as I have hardly started on mine, but I can tell you that your ability to create a successful portfolio depends a great deal on your current level of artistic ability. If you have a really strong background in "art" not "architecture", you could probably assemble something quite quickly. If you are like me, and have little "natural" ability, and no background whatsoever since sophomore art classes in High School, you will have a much longer road ahead of you. Do not be fooled by people on here who talk about natural talent. Artistic ability is often times learned. Some people start learning at a young age, others older. Best route in my opinion is take drawing 1, and some type of hand craft oriented class (sculpture, woodworking), and then move into an intense summer architecture program. These programs are fast paced, and usually require some design ability. I did it the other way around, and although I learned a ton, and significantly improved my ability to craft models, and draw, I had a harder time keeping up.