Depending on how comfortable you are/your pillion is:
a.) for new riders/pillions. Basically ride as though it's wet, accelerate more gently, brake more gently (you can use the back brake a lot more too with someone on the back without it locking), and don't lean the bike over as much.
Mounting, I get on the bike, both feet on the floor, get the pillion to put their left leg on the left peg and swing over. Once they're on and settled, I pull off - that's the only bit I'm not a fan of as with heavier pillions, the bars are much lighter than normal if you've not adjusted the preload to compensate. You'll probably want to tell them that before they get off, they need to check with you to make sure it's ok!
Cornering with people on I don't really find much different, slow speed stuff is a bit trickier, particularly u-turns.
General advice that you might want to tell first time pillioners - stay relatively still, particularly at low speed stuff. Stay behind the rider (and be warned, 95% of people i've had on the back for the first time have at the first corner, have leaned the wrong way to begin with).
If they're only little/particularly nervous, I'd get them to hang on around your waist, makes people feel more comfortable, but also means they don't tend to lean the wrong way as much if they do. For bigger guys/more experienced people, I prefer them holding onto the grab rails/grab strap as you don't get as much weight transfer onto your arms when braking (not particularly a massive issue with an upright bike, but was seriously painful with heavy people under heavy braking on my old Ninja 900)
That said, once you get used to it, you can have some great fun with people on the back, I've a few female mates who love it on the back that I take out quite often and I much prefer riding with them to riding alone - you have someone to talk to (i've got a set of headsets i use specifically for this purpose, they're also good for new pillioners as you can talk to them, let them know what you're up to and generally reassure them), which is nice for cruising along, and you can also ride quite hard, albeit it in a different way with someone on the back - you get a lot more rear grip, so you can accelerate bloody hard out of corners without the rear skipping up!
Personally, started at 7ish on the back of my dad's bike and loved it, he took it carefully to begin with, and now he's at the point where he doesn't really notice if I'm on the back really (which led to an interesting occasion once where he was grinding his footpeg out, having actually forgot I was behind him!)