I'm only new here (to most), but as I'm just about to start another new PC build this subject was on by mind and I thought I'd add my 2c worth.
For the person who is doing a first build and correctly installs all hardware in the case, usually they will be lucky and everything will work fine, but heaven help them trying to work out what is wrong if it doesn't and what a heck of a lot of work that is involved if it happens to be the motherboard!
I'm a firm advocate of "breadboarding" a new build. That is assembling all components one at a time outside of the case so as to test each component with mobo beep codes.
Starting off by Googling for the beep codes for your motherboard (if they are not in the mobo's manual) and then starting with installing the CPU and HSF (heatsink and fan) only, the main 2 power connections, then 1 stick of RAM, then 2 sticks of RAM (etc if more are to be installed), Video Card, plugging in keyboard and screen for access to the BIOS as sometimes the RAM setting need adjusting to their correct settings and then optical drive and HDD. Even installing the OS if you like. Each successful step should have a correct beep code when powered on. After the CPU is connected a beep code for a RAM problem should sound, because you haven't slotted it in yet or you might get a faulty CPU code instead if your unlucky.
An inbuilt mobo speaker or a small attachable one is required for breadboarding (easy to find from an old case or cheap to buy from a electronics parts store). A small screw driver can be used to short the ON/OFF connection pins or a connectible ON/OFF switch if you have one is preferred so you can turn the mobo power ON/OFF before and after each bit of hardware is added to the build. Never leave the power on when adding or removing a component.
Anyone who builds a lot of systems, soon discovers that about 1 in 7 (or so) builds comes with a faulty or even a DOA hardware component. The Breadboarding build method certainly saves a lot of grief and extra work if there is a faulty component (you know exactly what it is from the beep codes when it is added).
Everything working OK? Now start installing it all into the case as advised by this excellent thread with clear photos, knowing in advance that it will all work if it is correctly installed. This of course is a condensed description of Breadboarding, but step-by-step guides can be googled and should be followed, not this short description.
PS EDIT: Always keep yourself grounded