Liquids & Food
Keep them away from your laptop. Accidents can happen all too easily. Spilled liquids, crumbs etc will damage the internal components or cause electrical damage.
Beds, Carpets & Settees
Repeated use of a laptop here will cause the fans to suck up dust blocking the fan. Use a tray.
Do not Leave Your Laptop in a Car
Insides of cars experience large temperature swings that could damage a laptop, & a laptop is an inviting target for a smash & grab thief.
Plug Accessory devices into their proper slots
Jamming a device into the wrong socket could damage the sockets, making it impossible to use them again.
Antivirus Software
Is the best defence against a virus, which can steal your data or may also slow down the performance?
Protect the LCD display monitor
When you shut your laptop, make sure there are no items, such as a pencil, on the keyboard. These can damage or break the display screen if the laptop is shut on them.
Experienced Technician.
Every 12 months take your computer to a suitably qualified technician for a full maintenance check. It's a bit like getting your car serviced, your computer will perform better & last longer.