Fitting a SATA Solid State Drive to a PC
Firstly, you will need to find a good place in the case to mount the SSD drive.
It can vary according to your case - so to look around to see the best place on your particular case
Often cases will include a cage like the one below, and may already include a hard drive. Locate a free space.
Hard drives and SSDs can vary in size from 5.5 inch, 3.5 inch and 2.5 inch. It is possible you may need to buy a caddy. The images below show what this looks like and how a smaller drive would fit into it. You would then fit the caddy to the cage.
... - open the opposite side panel - you can have a look and the best place is to open the panel with the blue circle. 
If you are planning to have several hard drives, the orange circle is better - but
because the SSD is 2.5" and standard HDD are 3.5" you may need to buy one of these caddies to secure it in place.
Once in place you will need to identify the power cable, which should be coming from the loom of cables from the power supply, it will look like the black end of this cable here.
This will fit into the SSD hard drive onto the yellow circled power port below.
Once you have plugged the power cable in, it is time to identify the data cable. This should come with the SSD.
It usually (but not always) is a red cable. You will know it is correct if it fits! You need to fit it at one end to the data port (circled orange above) and the other to the motherboard.
Once it is on, it should look something like this. ( in the image below there are 2 SSDs and you only have 1) 
Once done, you will need to connect the data cable to the motherboard - I have circled the ports - any of these will work. 
I have also shown you on this diagram, the same ports
The red is the best one to plug into. The gold circled will also work. 
Once you have all this cabled up (you will need to weave the cables through from the side panel to the motherboard, and the SSDs are secured in place with the screws that came with the SSD you should be good to go.