Don't open dodgy files (like in emails), or if you must, do it in a VM. Run adblock and no-script on your web browser, only visit trusted sites. If you must, u

Don't open dodgy files (like in emails), or if you must, do it in a VM. Run adblock and no-script on your web browser, only visit trusted sites. If you must, use a VM. Don't download and install software you don't trust. Either it should be a big company in the news regularly, have good reviews from people you trust, or it should be open source. If you must use a VM. Backup your files regularly (and have offline backups, the data is the most important thing), reinstall your OS regularly (this gets rid of old and outdated software you don't remember; because I doubt you install all updates, have you updated Java recently? How about adobe flash or reader? How about the chipset drivers that likely came with your machine?).