What would be the best way to keep safe you Pc/Laptop from viruses/Trojan?

There are many ways to keep safe your PC but some are below:-

•  Install antivirus (purchased). Run every day and update when it require.
• surf only secure website
• Connect USB and without wasting time cancel autoplay then scan it after that open USB
• don't download files and software from unknown address.
• disable PC sharing to other PC if need then after sharing should scan.
• download files and softwares scan first then install or open

If above mentioned point you like just thumbs up.  

trojans uses windows script host could be disabled limit users permissions to prevent total damage good antivirus backup in case of failure 

off your computer and not used.

Jus be careful which sites you are loading. Imagine the internet as a large city and as any city there are famous suburbs as well as notorious ones.

1. Install a good quality Antivirus on your PC.

2. Maintain that Antivirus software by frequently updating it and allowing it to scan your machine.

3. Stay away from web pages with lots of ads or use a browser addon to remove ads on the webpage. I use (Adblock)