Measure a large piece of cardboard or mat board with your measuring tape. Standard portfolio measurements are 40 by 32 inches. Mark your measurements off with a pencil or marker to ensure correct trimming dimensions. Repeat on another piece of cardboard or mat board. You will need two pieces.
Cut along your measurement marks with a box cutter or straight razor for a smooth edge. Do not use scissors because this could produce a jagged edge, making it more difficult to create a polished, professional look.
Measure your fabric to double the measurement of your original board, for both width and length. Cut your piece of fabric according to your measurements with a pair of sharp scissors. Heavier fabrics are ideal for portfolios as they can easily hide any underlying imperfections.
Pin the fabric together at your cut sides, folding the fabric inward to create a smooth seam. Place your pins 1/2-inch apart until the entire edge of your fabric is secure.
Sew your fabric together, 1/4-inch from the edge on the long sides and on one width side, leaving one side open. Ensure that you create your stitches on your sewing machine on the pinned side. This is the inside of your portfolio cover. Remove the pins once you are finished creating a straight seam.
Turn your sewn fabric right-side out, smooth seam side showing. Insert your cut cardboard or mat board. You may wish to secure the board with super glue or a hot glue gun but this is completely optional. Stitch the open end to create a hem by hand, with 1/4-inch of the end of the fabric folded inward.
Place your artwork and artist profile sheet into protective plastic sleeves and slide into your portfolio for safe transport.