What are precautionary steps for malware detection?

You can take precautionary steps to prevent malware -

1. Install a good anti-virus / anti-malware software
2. Keep it (the anti-virus) software updated
3. Keep your operating system up to date
4. Scan entire computer periodically (every weekend) for any kind of suspicious software
5. Avoid inserting external pen-drives borrowed from friends
6. Do not visit non-trustworthy websites
7. Do not open email attachments from unknown sources.
8. Gmail typically prevents malware, but be extra careful while opening attachments. In general, open them in your browser in 'preview' mode.
9. Avoid accessing Internet on your phone or laptop from the public, free wi-fi hotspots. You never know which Internet connection you are connected to - it could have been disguised as authentic WiFi
10. Always use strong passwords for all your online accounts. 
11. Do not download software from untrustworthy websites. In general, you should avoid downloading cracked software.

Does this help?