Olly D wrote:
Is it as they say, tighten by hand as much as poss, and then one full
turn?

I always tighten until they creak or judder a little bit. Then put on
water. Any drips, tighten slightly. Note that brass olives need more
force than the copper ones. Also note, if the pipe itself is not
constrained in some way, often it will turn a bit as you tighen the
fitting, which can be a problem if orientation matters. I have never
had to use jointing paste, PTFE etc.

One thing that I always wonder about. Most of the fittings that come
with olives (service valves etc) seem to have copper olives, but brass
ones are more commonly available in packets. Explanation anyone ?

Good luck,
Simon.