You will need a caddy or bracket to replace the optical drive and install your present or new HD.
http://eshop.macsales.com/shop/drive_bracket/datadoubler/ Most people have the old HD installed where the optical drive was, and install the SSD in the original HD drive bay.
You will also need a Philips head screwdriver #00 to open the MBP and remove the single holding bracket next to the HD and a Torx 6 driver to transfer the lugs on the sides of the HD to the SSD.
See this current thread for some good info.
https://forums.macrumors.com/threads/1483083/
I also went shopping for a M4, my local supplier was out of stock, so I got an Intel 335 series 240GB, which has very good reviews,
http://www.pcworld.com/article/2013225/review-intels-series-335-delivers-more-ssd-for-less.html and is working well in my late 2011 MBP. After installation, you might want to enable Trim, I used Trim Enabler 2.1, no problems there. Make sure you run Disk Permissions repair after rebooting.
Once you get used to the speed of an SSD, it will be very hard to go back to a regular mechanical HD!
You also might want to disable the Sudden Motion Sensor, useless for an SSD, using the following terminal command:
disabling SMS is:
sudo pmset -a sms 0
I also used the following command to disable the writing to disk on sleep:
1. set hibernate mode to 0
sudo pmset -a hibernatemode 0
hibernationmode 0 is normal sleep, kept in ram nothing written to hdd
hibernationmode 3 is safe sleep, kept and loaded from ram, written to hdd in case of power loss
hibernationmode 25 is full hibernation, memory is written to hdd and then ram is powered off
2. delete the unnecessary sleep file to regain disk space equal to memory (saves the same amount of disk space as your RAM, eg. 8 GBs), since hibernate is disabled, you can use the Go to folder menu for that. The file is found in the /var/vm/ folder, and is named sleepimage. Reboot and simply delete that file.
Your MBP will work with 16GB and the price is not that much more than 8GB now, worth thinking about.
