I never quite understood the fascination with using cans of compressed air or other blowers. Credit the advertising marketers.

Grab any vacuum within reach and suck and trap, not blow and redistribute, the dust and dirt. If concerned with ESD, touch the laptop/PC metal chassis to ground yourself.

Brush attachments are nice, but the PC's interior will cope just fine if you are unable to remove every trace coating of grime; I'd stress maintaining a clean surrounding environment for the PC. A PC's electronics will attract and capture impurities in the air -- hence why you want to vacuum, not blow!