You can make your squares any size you like. I did mine at 5 inches because we did an exchange of 5 inch squares in our group. Sometimes you can order an I Spy group of fabric squares from on-line fabric suppliers. I have seen I Spy quilts done with 2 inch squares for carrying to the car or doctor's office. It makes a nice portable little game to play that will fit in your purse. Unless you are on a deadline, just have fun being on the look out for fun fat quarters to pick up as you see them. Good luck!