• Check if the power cable is properly connected to both the computer and the power outlet.
• Ensure that the power outlet is functioning by plugging in another device.
• Try holding down the power button for 10-15 seconds to perform a hard reset.

If none of these steps work, it could indicate a hardware issue such as a faulty power supply or motherboard.

• Check for malware and viruses using reputable antivirus software.
• Delete unnecessary files and programs to free up disk space.
• Disable startup programs that are not essential.
• Upgrade your hardware components like RAM or SSD for improved performance.
• Consider reinstalling the operating system if the problem persists.

• Immediately turn off the laptop and disconnect it from any power source.
• Remove the battery if possible.
• Dry the laptop thoroughly with a towel and let it air dry for at least 24 hours.
• Do not attempt to turn it on until you're sure it's completely dry.
• If the liquid spill is significant or if the laptop doesn't work after drying, seek professional help.

• Check for overheating by monitoring the temperature of your CPU and GPU.
• Update device drivers and operating system.
• Scan for malware and viruses.
• Test your RAM using diagnostic tools.
• Check for disk errors using built-in utilities like CHKDSK (Windows) or Disk Utility (Mac).

Clean your computer's exterior regularly with a soft cloth to remove dust and debris. 

Inside, it depends on usage and environment. For most users, once every 3-6 months is sufficient. Use compressed air to blow out dust from the fans, vents, and components.

If you're uncomfortable opening your computer, consider having it professionally cleaned.

It depends on the extent of the repairs needed and your budget.

If the repairs are minor and the computer meets your needs, it may be more cost-effective to repair it.

However, if the repairs are extensive or if the computer is several years old, it might be wiser to invest in a new one, especially considering the advancements in technology.

Remember, if you're unsure about any repairs, it's always best to consult a professional technician to avoid causing further damage to your computer.