Hi James
Now is the time to put it all into practice!
I strongly recommend that you use a checklist for your first visit to ensure that you cover all that you need to. Take your time, avoid jargon and work through it logically.
What I do is pick a fairly straightforward unit and show the candidate how he/she can gain the evidence for it, explaining the different types of evidence and the difference between knowledge and understanding and performance criteria.
I don't usually dive into cross referencing until we have our first piece of evidence to assess, it makes more sense then.
If you're a bit uncertain about assessing the evidence at first, tell the candidate that you will assess it at your next visit and then take it home with you and work through it at your own pace. You are bound to miss bits at first but you will soon learn to recognise where the standards overlap from unit to unit so that you can assess holistically.
If you are not sure about something, just say "I'm not certain about this, I'll have a word with my countersigning asessor and get back to you at our next meeting", rather than get it wrong.
I advise getting your countersigning assessor to have a look at the portfolios early on so any issues or queries can be raised quickly before too much evidence has been assessed.
There is only one tip about your candidate working nights - you will have to visit at night, it's as simple as that. It is the assessor's responsibility to arrange visits to fit in with the candidates working schedule, that's in the A1 standards.
Any assistance required, just shout.
Good luck.

Dave