This will explain how to manually install a Hard Drive, Cd-Rom, or DvD Rom into your computer Tower.
1. After opening up the box your hard drive came in make sure to check the Jumper Pins on the back side of your hard drive/cd-rom/dvd rom for proper settings. If you only use 1 hd/cd-rom/dvd rom you would want your Jumper Pins set on Master. If using 2 harddrives/cd-roms/dvd-roms you would want your jumper pins to be set Master for 1st Device, Slave or Cable Select for the 2nd device.
2. Once you have properly set your Jumper Settings check to make sure if you are Using IDE or SATA Drives. This is where you got to use the proper cables to install the devices. On an IDE Ribbon Cable you got 3 plugin adapters the single one on the farthest end goes into your motherboard, The Top on goes to the Master Device and the Middle 1 closest to the Top one is used for your Secondary/Slave Device.
3. Once you got your Cables properly hooked up now grab the white plugin supplied to you from the Power Supply and insert it the proper way into its Plugin space.
Once these steps are completed Turn your computer on and if no Operating System is present on any of the Drives install an Operating System of your choice. This is only for Hard Drives. You can use 2 different Operating systems on both your hard drives if you feel the need to set them up with different. Also you can dual boot your hard drive by installing 2 Operating Systems onto 1 Partition. Keep in mind though you need an Operating System on your Master/Primary Drive for it to work. The Secondary/Slave drive is not necessary to have an Operating System on if you know how to use DOS..
Keep in mind your all your devices need to be compatible with your Operating Systems, Motherboards, and other components before installing.
If I have left anything out feel free to add what I forgot as a reply, as for I just quickly typed this up.