The first and foremost thing you need to do is keep it dust free. Providing your laptop a good casing would do some good for its enhanced performance. Accumulation of dust inside the fan which keeps the CPU cool could prevent it from functioning properly and slowly it could lead to other problems.
Most importantly, how you carry and drop your laptop matters a lot. You need to be extremely gentle with your hands and electronics are very delicate items. Above all, do not eat in front of your computer. Small crumbs can easily drop in and spoil your keys and other components.
Never keep your laptop near electrical components as the magnetic field generated by the latter can harm your computer. Keep your laptop screen clean and make it a point to dust your computer regularly.
You should also move all the important files to an external disk. This would increase the occupied space which gives the memory to work free and fast. You need to keep updating your applications which you use regularly. The programs and applications which haven't been used for long should be uninstalled and deleted immediately as they affect the performance too.
Last but not the least, use the system defragging option. Defragging improves quality of space in the drive and increases the speed of performance. Following these tips given above can definitely help you improve the performance of your laptop.