I've done a number of brake line replacements in a shop, not on a VW but a
brake line is a brake line.

First I find where it's leaking & then see if there are any other lines
that look bad.
Next I squirt the bleeders with pen fluid.
Then I get a tape measure and see how long a line I'll need, then I get
that much (plus a little) and any needed unions.
I put the unions where I can get to them for a leak check.
Then I cut the old line an inch or so behind the fitting and if I can use a
socket to take the fitting/line out and put it aside.
Then I do the same to the other end, (drip pans to catch the mess).
Then I run a new line along the old, leaving the old line where it's at.
Most people don't want to pay the hourly shop rate to remove the old line.
If it goes over, alongside or some place I can't see I cover the end and
work it thru to the other side.
Bends are carefully made with a couple of wrenches. Carefully made, you
crimp it you start over.
Start the fittings carefully, you don't want to cross thread them.
Once everything is right I tighten all the fittings. Then I go along and
secure the new line so it won't vibrate or rub.
Then it's time to open the bleeders, fill the MC and let gravity do it's
thing (into a drip pan). Keep an eye on the MC level. After a bit the
bleeders are closed and you try the pedal, then the final bleeding  and a
leak check of everything.
Just a note- bleeder valve problems can add to the time/cost of this job,
just one of those things.