take the bottom rad hose off to empty that. get the stat out to empty the block. flush it through with a hose once you refill it, i expect it should be a self bleeding system (most golfs ive played with are) but ive not played with a 1.6
the way they self bleed is via a small water hose that goes back to the top of the expansion tank. if yours has that itll self bleed when you start to refill and have the engine running, youll notice the hose is returning air back to the expansion tank. once its almost bled, youll see coolant starts to pass back into the expansion tank. eventually it will be all coolant, no air, and its bled the car is ready to rock and roll
a 16v 1.6 mk4 has a drain tap on the bottom rad hose, so no need to remove hoses, in fact attach a bit of garden hose and you can collect it all to flush down the loo/sink, don't let it drain into a surface water drain, it doesn't do the fishes any good I'd imagine a 8v 1.6 mk4 is the same. not really any need to flush if what comes out is clean, the mk4's usually are. fill up with G12+ coolant and distilled water (battery top up water from halfords etc.)