Hi Gav
I'm surprised no-one has replied to your question!
OK on the Myford, lucky you, better than most of the chinese garbiage available (like mine)
There are a pile of ways to do this, here's what I do.
Let's say you want to drill 10mm exactly (actually, exactly is a waste of time, unless the shaft you have is under 10mm by about 10uM).
I normally chuck up the item in the three jaw chuck (four jaw won't centre easily) - do it a couple of times and check by eye that it is running true (your eye is really accurate). Using a centre drill in the (previously accurately centred) tailstock, drill the centre out.
Using an undersized drill in said tailstock (normal size will generally give an oversized hole) - say 9.8mm (you can buy drills in 0.1mm increments, see Axminster etc) - drill out the hub.
Using an accurate 10mm reamer in the tailstock, you have a couple of options - turn the chuck by hand while winding in the tailstock (preferred) or spool up the chuck and use the tailstock like a drill (bodger's method ).
There are a pile of other variables, speed/feed/lubrication that you need to take in to consideration. Of course, you could just drill it undersized then go the next size up
I would first suggest getting a copy of Tubal Cain's series on lathe work - ancient, but good practical information if you have never used a lathe properly (me neither
)
Cheers
Neil