Have you taken a look here:
Choose your Macbook Pro model and then it will show you the instructions on how to upgrade your RAM. It is a real easy process. To replace both RAM slots is the same method. So how it shows you to change the one module, do the exact same for the other modules. Both RAM slots sit next to each other.
A SSD drive will definitely improve the performance on your machine. SSD drives have faster read/write speeds, which will improve the performance.
I would recommend that if you wish to go this route, then go through to an Apple service centre for the upgrade. As if you do this yourself you void the warranty on your unit. Any certified Apple technician can do this upgrade for you. It's not a highly difficult task to replace the hard drive, but I'd hate it to mess up your warranty in case you need this at a later stage.