Mounting the Cartridge
Mind that stylus!
— Mounting the cartridge on the tonearm is just too hard. Is there an easier way?
— Fortunately yes. We have done a short video to explain how:

— How precisely do I have to align the cartridge? Will a 0.5 mm error make a difference?
— Micro Seiki, who obviously knew a thing or two about vinyl playback, advised in its manuals "A deviation of about 1 mm will not affect the tonearm movement or sound quality in any way". Getting it within a millimeter is fine. There is no need to chase every tenth of a mm or angular minute.

Remember, any adjustment you do is static. Once the LP is playing, forces will push the cantilever quite far out of the "ideal" static alignment.

— How tight do I need to screw the cartridge to the headshell?
— Hand tight is usually enough. The force you can apply while holding a small screwdriver with just two fingers is the maximum you should use.

— How important is VTA? How precise should I set it and how?
— Not very important. The variation of cutting angle between different discs is in the 5-10 degree range. The cartridge's manufacturing error is usually in the same range.

Rising or lowering the (typical) tonearm's back 5 mm will only give you 1.3 degree change in VTA. So "dialling VTA in" is a complete waste of time — it's impossible to change this angle enough to compensate for cutting variation and cartridge assembly tolerance.
Unless your cartridge has a huge assembly error that you want to compensate for, set your tonearm's height so that the upper surface of the cartridge is horizontal when the stylus is resting on the LP with correctly applied downforce. There's a cheap tool you can buy on Amazon or Aliexpress that simplifies the procedure a bit.

If you have a carpenter's laser level, you can also use it to ensure the cartridge's top surface is exactly horizontal.

Yes, this one is a bit off

— How do I set up the azimuth right?
— There's a short and a long answer to this question.

The short one: don't touch it unless you use an exotic handmade cartridge, or your tonearm's azimuth is off.

The long answer: we wrote an in-depth 3-part series on the azimuth adjustment: https://korfaudio.com/blog36, https://korfaudio.com/blog37, https://korfaudio.com/blog38. The detailed guide in in the last post.