I'm using MacBook Pro 2011 for the model of this guide. This guide might not apply to other MacBook Pro models.
Prepare your SSD, SATA Adapter, Philips 00 screwdriver, T6x40 screwdriver.
This is the SATA adapter. I got Anker because of good review on Amazon.
This is the SSD that I use. Samsung 840 Pro 256 GB. Just make sure your SSD is compatible with your MacBook
We'll be using both of these. T6x40 and PH00x40. I picked Wiha because of good reviews on Amazon (again) :)
Connect your SSD with the SATA adapter onto your laptop
Open up Disk Utility
Select your SSD. In your case, its drive color should be the yellow one / the mounted one (I forgot to take a pic when I did this, hence it's a bit different).
Select the Erase tab. Leave the format as `Mac OS Extended (Journaled)`. Feel free to change the name. Then just hit `Erase`. Don't worry about it since it's empty to begin with anyway.
Download this app called SuperDuper! to clone the content of your old hard drive to the new one. We want to have all the files from your old hard drive into your new one. Like, all of them!
Pick your old HDD to your new SSD. Select backup all files. This will take a while. I suggest doing this before you go to sleep.
Once it's done. You need to shut your laptop down and unplug your power source. Make sure there's no current goes into it.
Use PH00x40 screwdriver to remove the back lid of your MacBook
Your hard drive space is on the top left of the picture
Unscrew those 4 screws with Philips
We want to unplug this cable and plug this in into our SSD
If you have this sticker thingy, pull this out and put it on your new SSD
Unscrew those 4 torq screwdrivers
Put the sticker on your SSD so that it would be easy for you to pull your hard drive out next time you need to replace / change it.
Put the 4 torq screwdriver into your SSD
Plug the cable into your SSD
Place your SSD with the plastic sticker thingy into the space where your old hard drive was
Screw everything back into place and just boot up your laptop! It's gonna take a bit of time for the first boot
Download TRIM Enabler and turn the switch on, then restart your computer. If you don't know what it does, Google it :)
All done! You should notice the difference in boot speed and program launch speed pretty soon. Maybe restart or run repair disk if you need to and you should be good to go.