THE PORTFOLIO CASE
The Portfolio Case:
Spend the money and buy a proper portfolio case to carry and protect your work. These cases can be bought from an art supply store. They will come in all different sizes and quality. Consider this as an investment and buy one that is nice and will suit your future needs. You will probably have this portfolio case for the rest of your life or until it breaks or you loose it.
I personally like the cases that have plastic sleeves for inserting work. The sleeves will protect work from rubbing against each other and will prevent the work from being jostled around when walking and possibly getting damaged. These cases are usually more expensive. If you decide on a shell case, insert tissue paper in-between your works to reduce rubbing, smudging and prevent unwanted image transferring.