if you don't aspirate you will DIE !!! its true!! lol no i'm joking. aspirating or not aspirating isn't gonna make a lick of difference when you inject if you inject properly. get it into the muscle, inject slowly.. then pull out. just cause you aspirate and don't see blood doesn't mean you didn't go through a vein anyway and it doesn't stop you from pulling out and clipping a vein either. those of you that aspirate i'm sure have noticed that when you've pulled out you still had some blood regardless.
also the infection shit is way overblown too. you are 100X more likely to pick something up touching something at your gym than you are injecting. just make sure you inject will a new needle simply because those needles are so sharp and thin that they will quickly lose their sharpness at the tip, so if you accidentally put the capper on the tip swapping out a needle then you are best served getting a fresh needle put on in its place.. ya ya i use alcohol swabs on the area before and after but the chances of getting an infection if i didn't is slim to none lets be honest. i do it just for cleanlieness