Duke William of Normandy won the battle because was well prepared and had a good army. They prepared carefully for the battle. The Normans had knights on horseback who were skilful fighters.
A utility knife, metal ruler, and a hammer can be faster than trying to carefully saw an opening. Score the drywall a couple times till you are most of the way through, then just knock a hole with the hammer and break the drywall back at the score lines.
You can cut metal studs and tracks with a hacksaw or with tin snips, but professional framers often do it by fitting a chop saw with a metal-cutting blade. Metal framing joins together with screws -- not nails -- and drywall installers use self-tapping drywall screws to hang the drywall. Measure the length of the wall, using a tape measure. Cut two pieces of framing track to that length with tin snips. If the distance is longer than the stud, cut two smaller pieces of track to place next to full ones to span the total distance.