Piece of pee to do it.
First, in your case, READ THE INSTRUCTION MANUALS!! Taking the power supply out can give you more room to work but that depends on the case.
Insert the CPU and fit it's cooler before you fit the motherboard into the case as it can save scraped knuckles and gives you a nice lump to hold onto. Fit RAM before fitting mobo into case too as space could be limited. Make sure "jumpers" are set properly (if necessary, some mobos don't have that any more) before you fit the motherboard in the case. Fit motherboard in case next. Connect up things like "speaker"/hdd light/power/reset/usb panel/etc wires next. Fit all components after you fit the motherboard into the case, they'll only fit one way so if you have to force things you are doing it wrong so don't force anything. Once all components are fitted, add all cables. That's it basically. Oh, if possible, make sure it's easy to add anything else in the future (put your dvd drive in the bottom drive bay so if you add another it's easier to fit that in above the existing one, as an example). Many cables, etc, are now colour coded so it's even easier than in the past.
Ultimately, take your time. Patience is a virtue and since you'll spend so long installing software an extra few minutes doing the build will not make a difference to things.
Oh, make sure at least one part of your body is touching the case when you add things as static can cause havoc.