It's all entirely speculation but I'd have to guess they'd just take them to the train platform in Hogsmeade near the time in which the Hogwarts Express arrives, that way everything goes as normal from then on. Luggage taken care of and they arrive by Threstal carriage or boat depending on their year.
This is all contradicted by Pottermore, however, which states:
Many pure-blood families were outraged at the idea of their children using Muggle transport, which they claimed was unsafe, insanitary and demeaning; however, as the Ministry decreed that students either rode the train or did not attend school, the objections were swiftly silenced.
Pottermore - The Hogwarts Express
We do not know how relaxed this law can be, though, as we know both Harry and Ron attended school by Car in their second year and did attend school.
Also Headmaster Dippet mentions the possibility to Tom staying over the summer (in the diary flashback scene in CoS)
"The thing is, Tom,” [Dippet] sighed, “Special arrangements might have been made for you, but in the current circumstances…”
So clearly special arrangements can be made for those staying in the school, iI would definitely say that permanent special arrangements can be made for those living much closer to the school.
(Thanks to @BMWurm for finding the quote special arrangement)