The "definitive" list has just been published, hoping the B52 shows up!http://www.jerseyairdisplay.org.uk/news/showarticle.php?articleID=152
If I remember rightly, arrivals are usually a day or two before, with some practice displays on the Wednesday. There are a few departures on the morning of the display for the Guernsey display, which is usually before/overlapping - last time I was around for it, I was up at the north of the airport for the BBMF take off and return and was able to cycle down to St Aubin's bay for the display with plenty of time to spare. I wouldn't have pushed the time so much in a car though as traffic can get quite bad. I think most aircraft leave the morning after to allow for the static on Thursday evening, although there can be a few departures that evening.
Outside the static, viewing (or at least photography) from the airport is a little tricky due to the high airport boundary fence, but there's apparently somewhere to the south of the airport, near the west end of the runway that's quite good.
The display itself can be viewed from anywhere in St Aubin's bay. The display line is quite far out (usually marked with life rafts/bouys) and I'm not sure on what the rules are with regards to viewing from Elizabeth Castle or St Aubin's fort (south of the display line). Viewing from the beach (apart from a small area in front of La Figate cafe) isn't possible and I think the Elizabeth Marina pier/breakwater is out of bounds too - the closest you'll get to the display line is probably just outside the Radisson hotel, but I've heard of over-zealous marshalls around there in the past.
Enough of the negatives though, it's usually a very good display, especially if the weather's good