After you've gathered all your parts, you should begin to unbox them.
After that, preparing the parts for installation is the next step.
Most of the time the only tool you will need is a Phillips screwdriver.
One major step is to make sure you've grounded yourself before touching any of your components. If you don't, you run the risk of shocking your parts and rendering them useless. Grounding yourself is as easy as touching the back of the computer case (the metal part) or using an anti-static wristband.
Start off with taking the side panels off your case. these are usually secured with thumbscrews on the back of your case. After that, you should pull the side panel off (slide it toward the rear of the case) to expose the internal section. Repeat with the other side. Make sure to keep the thumbscrews in a safe place so they don't roll away somewhere.
Now you should decide what to install first. In my case I installed my Hard Drive, Solid State Drive, DVD Drive, and LED controller panel.
My case had pull out Hard drive trays so I started by pulling two of those out and placing them aside. Next, I took my hard drive and matched the hole in the sides of the drive to the tool-less installation drive tray (small bumps in the tray). I pushed it in (I had to bend the tray a bit) and slid it back into the case. I then took my solid state drive and found holes in the bottom of the tray for screw mounts. The screws do not come with the drives, but with the case itself. since the solid state drive is technically a 2.5" drive, using those screws would probably be to your best interests. Putting in the screws diagonally will be the best way to install nearly anything in a computer and here is no exception. I then slid that completed drive tray back into the case as well.
It is important to know whether the plugs on the drives are facing rearwards (opposite from where you are pushing them in) so you can plug them in without excess clutter.
You should now screw in the standoffs into the case. Afterwards, place the motherboard onto the standoffs, making sure to line up the ports in the back to the I/O shield.
There should be slots below the area around the CPU. These are your expasion slots. Technically known as PCI or PCI Express slots. there are short ones (PCI x1) and two longer ones. The one that is slightly longer than the other is most likely the PCI Express 3.0. This slot is where most modern video cards should be seated. The other is the PCI Express 2.0. These different slots do have different speeds, but usually the slot higher up has the higher speed (x8 or x16 for PCI Express). This is important to note when you have 2 PCI Express 3.0 slots, like I do. A second slot can run a second video card (if the motherboard, power supply and existing video card support it). This is usually called Crossfire (AMD Video Cards) or SLI (Nvidia Video Cards). I have a single Nvidia GTX 770, plus my motherboard and power supply support SLI so I could add a second GTX 770 in the future. Before you stick the card in, you should check to see which expansion slots in the back of your case to open. It usually is 1-2 slots for most video cards. These are usually held in by thin sheet metal or screws. If it is the sheet metal, take care in remembering which slots must be removed because these usually cannot be put back, unlike screw secured panels. once you settle the video card onto the PCI Express slot, you should secure the bracket (pert that sticks out of the back of the case) with a provided screw (usually) so the card does not wave back and forth and damage the connector.
Now all that is left to do is to plug everything in. The cables are usually somewhat labeled, but the motherboard needs 2 cables from the PSU: and 8 pin CPU power, and a 24 pin main power. the drives all need a SATA power cable, and the video card usually needs 1-2 6-8 pin cables.
Now you should hide as much of the cabling away as possible (usually a place behind motherboard plate to tuck cables) and close both side panels. You should now be done building your computer!