After every few uses, it’s a good idea to open up all the parts of the machine that accessible (meaning you don’t need a screwdriver to open them) and get the tip of a canned air straw in there to blow out the dust. Now, much of the dust will still get trapped inside the case of the machine, but it will at least get off the moving parts for the time being. Things such as tension plates tend to get gunked with thread fuzz, which pushes the plates further apart, so they no longer grab the thread. Follow the thread path with the canned air to give it a quick cleaning!
They do make these teeny tiny little attachments that fit onto the end of your vacuum hose that can reach inside those open-able places in your sewing machine to suck all the air out. I myself just use a straw that I tape to the narrowest nozzle. I find this works beautifully especially in my overlocker! This is a good idea to do every month or so after you have been blowing the fuzz around with canned air every few days. Suck all that gunk out!
Most of the newer machines on the market today are self-oiling, but be sure to read your manual to make sure. Some machines have 3 to 5 points that need to be lubed with a drop of oil every few uses. If your machine came with a little tube of oil, chances are you need to oil it to keep it happy.
Once a year, I like to take my machine to a professional to have it cleaned. Cleanings can run anywhere from $100 to $200 depending on the machine and where you take it. Yes, I know that is a pretty price to pay, but here is why it’s important: The lubricants they use in the larger joints of the machine dry out over time and lose their viscosity. Left without maintenance for years upon years, this stuff essentially turns to glue! Ick!
I have a great machine maintenance man that I go to in Cheltenham and I am happy to recommend him if you contact me on firstname.lastname@example.org
You will notice when you have left your machine too long without a professional cleaning. Symptoms include a stiff handwheel, changes in stitch length, skipped stitches, loose tension, and groaning noises. This is especially important if you live in a dry climate, as the lubricant dries out even faster! Be kind and keep your machine hydrated!
Do a combination of these things for your buddy, and you will both have a long, happy relationship and MANY years of sewing to enjoy together!
Happy sewing (and cleaning)!