Keep in mind that changing or adding RAM at home or in unauthorized place or by an unauthorized person may cause losing the warranty. But if you are 100 % sure what you are doing or you do not have extra money to give to a specialist, follow the steps and advices that are next. May be you can do better than any specialist. Who knows?
First of all you have to decide what exactly you will need and choose the proper RAM memory. In case you use wrong RAM memory you can cause miss starting of the laptop or can cause problems and difficulties in the normal working. Your laptop can start bugging and can become slower than normally.
How can you know what RAM you need? You can look for information in the user manual of your laptop or in the web site of the producer or can use software like Everest to analyze your laptop. If you cannot find useful information, the advice is simply to open the laptop and to see what the RAM type inside is. Problem may occur with Apple machines, as there are only couples of proper RAM memories for this brand. If you want a RAM memory with good quality try to use the so called Apple RAMs, Mac and its Kingston type.
The second step after choosing the RAM is opening the laptop. Of course you have to turn it off; of course you have to wait the laptop to be cool enough. Take off the battery and with small screw unscrew the studs. The memory should be under the keyboard or in the bottom side of the corpus, which is most likely. If your laptop is with the second variant turn the laptop and find the lid for opening which may have a small painting of the RAM.
The RAM can be taken easily by rising the key and pulling the memory. It should happen easily.
Take the new memory and put it at the place of the old one and be sure to put it the right way. Raise the keys from the both sides. If you sure you have done everything properly, you can close the panel, attach the battery and start your laptop. You can again use Everest and can check if the new RAM is being indexed correctly.
Voala! You have new RAM!