Originally Posted by lalaland

If you have a mechanical machine, you will need to oil it and clean the bobbin area

If you have a computerized machine, about all you can do is keep the bobbin area clean.

If I'm working on fabric that throws up a lot of dust or lint, like flannel or fleece, I clean the bobbin area a couple of times during the project. If it's a big project, I'll clean it more often. If I'm working with cottons or blends, I clean the bobbin area after the project is complete.

Also if you're paper piecing your needle needs to be changed more frequently.
My machine tells me when the bobbin area needs to be cleaned - it stops working until I clean it.
Read your manual, there's lots of good info. in there.
I don't change my needles until they "talk" to me. A needle that makes a "thawcking" sound while you sew needs to be changed.

And read your manual. Amazing things, manuals, really good ones even give you wonderful sewing tips!