PSU = Power supply unit, MOBO = Motherboard, RAM = Random Access Memory, SSD = Solid state drive, HDD = Hard disk drive, ODD = Optical disk drive, GPU = Graphics processing unit (Graphics/ Video card).
Never use Rosewell products (Newegg owned brand that has terrible business practices, RMA nightmares, etc.)
Most PSUs are not made by the company you think you're buying them from.
A K at the end of your processor (ie: 4670k) means it is unlocked and able to be over-clocked (set to run at higher specifications than it's rated for).
Avoid Logysis products for case lighting/ cold cathodes especially they are known to hurt people and damage components.
Never trust the adhesive on LED/ Cathode/ Case lighting products, always secure them with clips or zip-ties.
Spend a lot of time on good cable management, it will increase airflow in your case, reduce dust build-up.
Whenever building or handling components of your computer wear an anti-static wrist band.
Never set computer components on carpet, always on their cardboard boxes, or your case sides.
Always measure out components such as GPUs and PSUs before buying for your case/ build to make certain they'll fit.
It's a good idea to buy a can of compressed air with your build to be able to regularly clean it out.
Tools you should always have to complete a build include: A small phillips and flathead screwdriver, plenty of zip ties, electrical tape, a flashlight (LED for brightness), a wrench/ needle nose pliers, tweezers.
Mounting a processor isn't as hard as everyone makes it sound, just lay your arm on the edge of your case and keep a steady hand, making sure not to bend any pins.
You'll be afraid to use too much force during your first build but some components such as plugging in your 24-PIN ATX cable to your mobo from the PSU, inserting in RAM, and pushing down the safety clip (not inserting it into the slot itself!) to secure your processor will require a bit of force.
Always save all spare screws, cables, etc, you never know when they'll come in handy.
I use my boxes to separate items, all receipts from a build in one box, all extra parts in another.
KEEP the anti-static bags components come in.
Keep all boxes from your build for 30 days incase you need to return or RMA something.
DO NOT spin fan blades while they're plugged in and power is enabled to your computer, it could produce a current and break other components.
YOU CAN use a 3-pin fan connector on a 4-pin outlet on the mobo.
Use gold-plated hdmi/ dvi/ vga cables for the best results. I had a GPU that kept crashing during games and it turned out to be the HDMI cable, tried a gold plated one and it worked like a charm ever since.
TI boost cards for GTX series really only usually gives a 10% performance increase and aren't worth the money.
Cheap USB wi-fi adapters will usually burn out fast.
ALWAYS monitor your internal temps, Asus mobos provide great software for this.
8 Gigabytes is the "sweet-spot" for RAM, I wouldn't recommend getting less then that, at least 8.
Get at least a gold-rated PSU as opposed to bronze, especially if investing a lot of money into your build, or if you care about the longevity of your parts, though bronze rated work just fine as well.
Corsair (RAM, PSUs, CPU coolers, Fans, Cases) Seasonic (PSUs) Gskill (RAM) Intel (CPU) AMD (CPU, GPU manufacturer) Coolermaster (Cases, CPU air coolers, Fans) Crucial (RAM, SSDs) Samsung (Monitors, SSDs, ODDs) Western Digital (HDDs) Bitfenix Co Ltd. (Cables, LED case lighting, Cases, Fans, Cases) Asus (Motherboards, rebranded GPUs, ODDs) Nvidia (GPU manufacturer) Sapphire (rebranded GPUs) EVGA (rebranded GPUs) LiteOn (ODDs) Asrock (Motherboards) Arctic Silver (Thermal paste, Thermal paste remover) Kingston (RAM) Silverstone (PSUs)
Again these are all personal opinions, do not take them at face value, do your research as I did mine and find what works in your budget and what works for your build, hopefully this information helps you.