First, use a turkey baster or a syringe and suck out the fluid from your clutch fluid resevoir. Then top it up with new fluid. That should help minimise the grit that would damage the master cylinder seals if you had pumped all the old fluid through.

Then look for the slave cylinder. It is just under the intake manifold, above the starter motor. Remove the rubber nipple, being careful not to drop it. Then attach some clear hose (I use PVC hose from Bunnings) loosen the nipple and get your friend to pump the clutch. You should see the old fluid come out through the tube. If you don't, then undo the nipple a bit more. Keep pumping under the fluid in the resevoir has gone down but is still above the minimum level. Top up and repeat until the fluid coming out is clean.

When you are comfortable that you have pumped out enough fluid, get your friend to do a final pedal press and hold it down. Tighten up the nipple (your friend can release the pedal after that) and carefully undo the tube so that you don't spray brake fluid on your nicely painted surfaces. Replace the nipple cover, top up the clutch fluid to just below the max level and close the cap.