To speed up your slow PC first step should be restart. In fact you should restart the computer before performing any of the below mentioned steps. Its just like the human brain. You need restart when you are tired.
- Stop all unused applications
- Turn off unneeded Desktop Features that try to make things look better.
- Do a shut down/reboot also known as a cold reboot.
- Empty the Recycle Bin.
- Uninstall all applications that are no longer needed.
- Run “Error Checking” on all hard drives.
- Run “De-fragment” on all hard drives
- Install anti-virus software and keep it current.
- Find and Delete Temporary Files.
- Set your computer’s energy settings to High Performance.
- Clean Up Primary Partition.
Need detail information of any of the step. Do let me know?