Ok so unfortunately, your CPU is soldered to your motherboard so there is no way to upgrade it... Same thing with your GPU. The only thing I can recommend is an external GPU, which you can read more about
here.
The drawbacks of said method is that one they are expensive, and two it requires an external psu(desktop grade) to power the card...
The only doable internal upgrades are ram and HD.
Ram:
For an upgrade from your current 6 to 8, I'd recommend these:
8 GB $37
For an upgrade from your current 6 to 16, I'd recommend these:
Crucial 8GB Kit $66
The reason being behind the single stick of 8GB, and not a dual channel 2x4GB configuration, is so that when you want to go to 16GB later you just pick up another stick and don't have to get rid of your current kit.
HD: So I don't recommend upgrading this because of all that can go wrong with backing up, and it's not even really worth the hassle unless you can afford a large capacity SSD....
So In conclusion, the only really useful upgrade that is possible on your laptop is the RAM, and an external GPU.
Good luck!
Signal