A potentially handy tip if you're constantly logging onto various different WiFi access points while doing your job.
I’m sure you all know this, but you can change the order that Wi-Fi networks are joined on your laptop, which is especially important if you have several access points at one place and need to prioritise which one is joined first.
Just go to System Preferences | Networks, choose the Wi-Fi on the left-hand side and then press the Advanced button. On the Wi-Fi tab, you’ll see a list of Wi-Fi base names; you can click on these and move them up and down the list.
It’s well worth clearing out this list every few months, especially if you travel a lot with your laptop – mine becomes choked up with a huge number of hotel names, airport-lounge logins and so forth. Don’t delete those you may visit again, since it’s comforting to find that you’re automatically logged in when you return to a hotel or airport lounge – if they haven’t changed the password, that is.
Another config setting worth checking out lies under the Users & Groups icon: click on the Login Items button to see which things are automatically started when you log in. Pruning this list can speed up your startup process and ensure that you’re not running a heap of unwanted crud in the background.