First of all. You
cannot, cannot, cannot RNG anything in HG/SS untill the dudes in the RNG thread over at Smogon figure it out first. It's just not possible yet without the use of... stuff I'd get "infracted" for even mentioning... >
You
can however RNG eggs in DP and Pt with just your cart and the RNG Reporter (that thing you downloaded).
You still need to be more specific though.
Are you trying to get an egg with whatever Nature/Gender/Ability/
Shinyness that you want, or are you trying to get the egg to have whatever IVs that you want? They require 2 different sets of steps.
And by the way. You seriously do need to read the OP over on smogon
completely first. There is seriously no simpler guide out there yet (until I write one XD soon).
Here's a little something to get you started though.
EVERY SINGLE ATTEMPT TO RNG IS ALWAYS BASED ON THE VERY FIRST STEP OF LEARNING TO RNG, "CALIBRATION".
Before you can even begin to think of all the wonderful pokes that you want to RNG, you
MUST, MUST, MUST figure out what your "average seconds" and "delay" are. They are different for every single person, so every single person has to do it for yourself.
Here's a great vid that helped me to understand "how" to calibrate.
[edit]
Here's another great vid that explains "calibration" pretty simply.