Also....If you aspirate and hit a a blood vessel no big deal, it happens. I've done it a few times with no pain the next day. Take the pin out and apply pressure to the area for a few moments and massage it a bit. Then just move to another site and pin there.

Also...a flow rate of approx. 30 sec per cc would significantly help reduce PIP as it gives the muscle time to find a space for the fluid.

First, you´ll need to draw the steroid out of the vial, with a syringe. The most common size for injecting juice is a 22-23ga. X 1-1.5" needle. This size will work for all water based and oil based injectable juice.

Next, make sure the top of the vial is clean, and swab it with an alcohol pad.

To draw the liquid out of the vial, you´ll first want to pull some air into the syringe, equal to the amount you want to draw. This pressure helps push it into the needle and doesn't create a vacuum.

Next, you want to hold the vial upside down and inject the air into the vial. This will increase pressure inside the vial and allow the liquid to be drawn into the syringe more easily. Once you´ve one this, and while you´re still holding the vial upside down (you need to make sure the tip of the needle is below the level of the liquid), slowly pull back on the plunger and draw the liquid into the syringe.

Next replace the needle that breached the rubber stopper of the vial with a fresh needle. This is because it will blunt the tip of a needle and the potential to cause additional discomfort when you inject.

After you have replaced the needle, you´ll need to swab the area you are about to inject with a new, clean, alcohol pad.

Anyway, after the site has been wiped with an alcohol pad, you´ll want to relax the area, and if possible, stretch the skin taught with your thumb and forefinger. This will make , the skin tight and provide an easier injection.

Once you have the skin stretched, while holding the needle like a dart, insert it with one swift motion, all the way to the end of the needle. Do this at a 90 degree angle relative to the muscle you are injecting.

Next, before doing your steroid injections, pull back on the plunger slowly, and check that no blood enters the syringe. As long as no blood has entered (not a a blood vessel), and that this is a good injection continue, push down on the plunger slowly with a slow, steady pressure.

Once the syringe is empty, pull out the needle with one swift motion, and put pressure on the area with a sterile alcohol pad. Then massage it a bit.

Next, simply apply a bandage, recap the needle, and dispose of everything in a safe manner.

A safe manner being destroy the evidence do not throw away with your trash that can be linked to you. ;)

I saw your stats. You can get by with the 1" at your size, but standard practice is 1 1/2" when you are doing your glutes. I think you should be fine with your 1", just make sure you are getting into the muscle and going all the way in with the needle.
Also, when you post your cycle, you are going to get many people saying you need to eat more and get your weight up. I would agree with this. Gear is not the answer in most cases. I'm a bigger guy and I would not gain any weight on gear, unless I really ate properly. There are lots of great posts in here about proper weight gaining diets. Spend some time looking in there.