The absolute best 2 pieces of advice I ever got when I got my sewing machine came from Dan when he told me to take the machine down to a sewing machine service center that works on industrial machines and have it gone over, and to throw away any thread and pre-filled bobbins that were over a year old.
I took my Juki in and had it serviced ($90) and it works great. They took it apart and cleaned it, checked bearings and bushings for excessive wear, lubed everything up, set the timing, and a few other things. I dropped it off on a Monday and picked it up that Friday. It hums right along.
When you go to pick the machine up, ask to talk to the tech who worked on your machine. That's the time to ask him (her) to show you exactly where to oil it and how often. Also ask if there is anything special you need to know about maintenance of that particular machine. I did that when I picked up my machine, and he gave me some great advice for keeping it in good running condition. His first piece of advice was to make a cover for it to keep dust and schmutz out of it when you're not using it (a great first project, BTW...)
I doubted Dan's advice to toss all the thread and bobbins until I got a new spool of thread for a project, and boy did it make a huge difference in how smooth the machine runs. If you absolutely know that the thread and bobbins are fairly new, you might be okay, but if you aren't sure or have reason to believe they're old, toss 'em and get new thread. It really DOES make a big difference.