"Just do it"
How I did it: First of all, I really needed to do since I'm applying for art schools. I gathered up my art and took digital photos of them. Then I picked out my best photos of my best art and took it to walmart to get prints made. Then I stuck them in the portfolio book I had for the longest time just for this.
Lessons & tips: It doesn't take long once you do it.
Start with the largest one. I just finished up my largest portfolio that needed at least 30 pieces. Most other portfolio requirements are only around 5-15 pieces. Since it's already gathered, getting the smaller portfolios together is MUCH easier
Resources: Itoya profolio
My boyfriend (he helped me physically put it together)
Wal Mart photo center