Unlike your rear wheels that drive your vehicle forwards and need to be torqued down to 250 ft lb, your front hubs on your beetle or bus essentially just spin so don’t actually need to be torqued down.
The method for tightening your front hub is as follows :
For a quick video guide click here
1) Presuming you have re-greased your bearings, slide your disk or drum back on to the spindle ensuring the bearings stay in place.
2) Slide the thick groved thrust washer on to rest against the bearing.
3) On splitscreens you then add a nut, on any later aircooled you add a locking nut. Tighten these down by hand with a wrench and pinch up. This is to ensure the bearing and hub seats correctly.
4) Loosen it off so the thrust washer can be moved with a screwdriver.
5) At this point on a splitscreen only add a lock washer and then another nut.
6) Tighten a little and check if you can move the thrust washer with a screwdriver. Keep tightening little by little until you ‘just’ can’t move the thrust washer. It may take several attempts but the is the best way to tighten the hub.
7) On a splitscreen bend the lock washer tabs to lock in place. On the later locking nut tighten the grubscrew down by hand. 
8) Finally fill the hub cover with grease and and tap it back on with a hammer. If you have the Speedo cable coming through, feed it through before tapping home and retain it with a circlip. Job done.