I just finished a 10 week cycle and started HCG on Monday.
I had 2 5000iu vials to use.
Here's how I'm using mine:
I mixed one of the vials and drew the contents into a syringe (I had some 1 1/2" 25ga syringes left over from my cycle)
The total contents was exactly 1ml - the first day I shot about 1/5 of the contents intramuscularly. Everyday since, at the same time of day, I shoot about 1/5 of the contents. I will continue to do so until the first batch is gone and then do the exact same with the other batch. This will work out to 1000iu per day for 10 days.
I am using the same syringe for the entire batch -- I simply change the needle immediately after I inject, and put the syringe back into the fridge. The bacteriostatic water content in the HCG will prevent any problems.
I am using 20 mg/day of Nolva along with the HCG, and after three days, there is a noticable difference in the size of my nuts.
You can shoot sub-cutaneous with a very small insulin pin, or go intramuscular -- either way will work. I have never done a sub-Q injection before, so I just do I.M.
I also waited 10 days after my last enanthate shot to start HCG, and I did a ton of research before starting. Good luck bro.