Well, congratulations!
Always nice to see a fellow JUBer get a new addition into the family.
As for advice....Well, I'm no father...So, I'll just pass one some tidbits that my father and grandfather had passed down from me through the years.
1.) Remember son, procrastination is like masturbation. It's fun at first, but in the end you're only fucking yourself.
2.) Never place the firewood under the trailer hitch on a camping trip, and then abruptly stand up when some one calls out for you...(Oh Grandpa....

)
3.) Never be the kinda person who walks around asking other people if it's warm enough for them. IF you're warm, chances are they're pretty warm too.
4.) Always remember, the rain in Spain stays mainly in the plains.
Alright, so maybe neither my grandfather nor father said No.4....But I consider Henry Higgins a damned good father figure....As long as he doesn't actually try to raise the child without Pickering or Mrs. Pearce there to keep him in line.
And now some advice for you:
From my limited amount of babysitting experience, I've learnt a few things.
Simple distractions tend to be the best way to keep a young mind occupied. Don't over due it, but don't just dangle your keys at them.
Reguardless of singing ability, a verse or two of "Wheels on the Bus", "London Bridge" or "Ole' McDonald" tend to quiet even the fussest of babies...If only for a moment so they can giggle at you making a complete fool of yourself.
Expect the crying. Sooner or later, that adorable little kid is going to let out some ungodly sounds...The best thing to do is try and figure out the why behind the cry, and take it from there.
If the crying is related to a fall or anything where they feel they've been hurt, a song or a razzbury to the stomach tends to quiet them as well. *You should only do the razzbury as a parent, not as a babysiter...
Well, that's all I can think of at the moment. Hope that helps...
Although, I will mention again: I am not a parent.