One of the major Christmas presents at my in-laws was a shiny new 13-inch MacBook Air that replaced a 2010-vintage MacBook–which meant that one of my major presents was getting apps, data and settings transferred from the old Mac to the new one, then completing the rest of the setup.

The first hiccups came in OS X’s Migration Assistant: It estimated the data transfusion would take five-plus hours over the home WiFi. But neither machine saw the other over a faster Ethernet link (using a USB-to-Ethernet adapter on the Air), and an ad hoc, computer-to-computer WiFi network didn’t work until I resorted to the un-Mac-like workaround of turning on Internet sharing on the source laptop.

Then I realized the work Migration Assistant had left for me: configuring parts of OS X Mavericks (preloaded on the new MacBook) and Yosemite (promptly installed as a free update) that had no equivalent in the old MacBook’s Snow Leopard, then changing OS X settings that would confuse anybody used to that five-year-old operating system.

Atop the first category: the social-media integration Apple began adding to OS X in 2012’s Mountain Lion release. My in-laws aren’t on Twitter and don’t spend much time in Facebook–but that integration’s ability to share a photo to Facebook from the Finder does address a pain point I’d heard from them.

An Apple ID is far more important in Yosemite than in Snow Leopard, courtesy of so many updates running through the Mac App Store. So I had to verify that hitherto-dusty account worked and had current billing info, without which we couldn’t download the free Yosemite update.

Migration Assistant had siphoned over a few long-ignored PowerPC applications that OS X hasn’t been able to run since 2011’s disappointing Lion, so I had to delete those myself.

I thought I was done at that point, and then I heard my father-in-law complaining about not being able to scroll. He had bumped into Apple’s foolish decision to make scroll bars invisible until you mouse over them or use a two-finger gesture to move up or down the page. I hadn’t thought to fix that setting (open System Preferences and click “General”) because I’d fixed it on my own Mac after maybe two hours with Lion. Oops.

The last round of settings to change were in the minds of Yosemite users who had been used to Snow Leopard. From that perspective, the Notifications icon at the top-right corner of the screen means nothing (and requires tweaking to avoid info pollution), while Launchpad’s rocketship Dock icon doesn’t exactly shout that you no longer need click around the Finder to run apps that aren’t already in the Dock.

I’ve spent a decent amount of time walking my wife’s folks through those angles, but I suspect I’ll be getting questions about the new computer for months to come. See also: “the gift that keeps on giving.”