The only thing you should worry about cleaning right now is the barrel, if you REALLY want to, this is not real steel lol. Don't touch the mechbox until you are completely confident, or have a gundoc you can send it to if you mess up. :P
Just find a takedown video and follow it to the point where you can remove the barrel. Your q-tip train should work, I have done it :P I would suggest getting a real cleaning kit though, much better.
As for oil, stay away from anything that eats rubber! Stick with silicone, I personally use the the 1.5wt oil i got with my gungas kit from airsoft innovations. It is a fairly common suggestion here to get 'shock oil' from an RC shop.
In this case, the oil is just there to pick up dust and other crap that is in the barrel, once you finish cleaning it, get the oil out! You do not want that stuff sitting there lubing up your BBs!(make sure to remove the hopup unit as well, you dont want oil on that either unless your soaking it)
Good luck, and welcome to airsoft!