Where should an expansion tank be plumbed in? Which bit of pipework?

I plan on using any available one with my XFlow. What are the do's and dont's here. I mean short of 'don't drink from it when hot' or such jokular responses!

Does it matter how far away from the main system?
On some cars you have to raise the tank to fill and bleed the system as the tank is situated lower than the heighest point in the plumbing.

What's the tried and tested arrangement?

The expansion tank should always go in the feed hose to the water pump imo. That way there is always some water pressure to prime it.

It should be bridged between both of the engines largest inlet and outlet hoses.
Eg. the larger inlet on the expansion bottle should go on the lower hose to the engine and the smaller one should go on the hose from the hose from the thermostat.
In otherwords there is always a small flow of water through the bottle.
This will speed up filling and puge any air.