You don't need the neighbor's help. It is a simple thing to accomplish. The process is the same as installing new memory. There are many instruction sources on the internet. I am providing a link to www.Kingston.com.
It is important that power is not on when this is done. That is why they say turn power button off and unplug the computer. It is also a good idea to touch the inside metal of the case to eliminate static charge when you touch the electronic components.
Then do the following:
1. Remove left side cover of your PC.If problem remains, we will move to additional suggestions.
2. Lay computer on its side so that you can access the internal components from above.
2. Locate memory. Your computer will have one to four "sticks" of memory sticking up from the motherboard (illustration can be seen at the Kingston link, above).
3. Remove memory, one stick at a time releasing end retainers. Gently remove memory and then reinstall it by pushing it down into the memory socket. you will know when it is fully seated when the end retainers move to the lock position. Sometimes you will hear a click. Continue with each memory stick. Once completed, plug in power cord, turn on power and attempt to boot. You may find that this has fixed your problem.