For simple objects like computer keyboards, you can use an aero dust spray to blow dust off. You can do the same for bigger, more complicated machines such as a sewing machine or refrigators, perhaps with a bigger spray can. Some people wouldn’t advise it though as it can potentially blow dust and dirt further inside the machine, getting the bits into hidden corners of the
case.
Truth is a good air spray is very advisable if your machine has openings where the dusts and dirt can be blown out into the floor. Most home machines however won’t and, as such, would need to take on other options.
A good stiff paint brush is always a good idea for brushing off dust. A small handheld vacuum cleaner is also a popular choice. Most handheld vacuum cleaners have tiny attachments that you can use to siphon out the dirt out of those little nooks and crannies.