Without using a rotary cutter it is a little more time consuming but it can be done. Try measuring in 2.5" (or whatever width you need) from a straight edge of the fabric & marking with a pencil or washable marker. Make a dotted line (as close or far apart as you need so that you can cut a straight line). Do this for only about 12" & then cut along your dotted line. Once you have 12" x 2.5" cut your can fold it over & line it up with the straight edge going up the the length or width of material (whichever you're doing). Use the original "measured" 12" x 2.5" (now folded over the next area to be cut) as your guideline to cut a further 12" x 2.5" to make a continuing piece. Open that piece up & line it up with your edge & your next piece to cut (using the growing length will be 24" x 2.5" & so on until you get the total strips of length you need. The trick is keeping your edges lined up & not cutting into your original material that your are using as a guideline. For real long lengths a pin here or there may help. That was hard to discribe...hope it's not confusing!!