Don't freeze HCG, but do keep it refrigerated once it's reconstituted with water. It's unstable once reconstituted...some say it's good for a month, others 40 days, others 60. A 5,000iu vial gives 20 doses at 250iu/dose, which will last you right around a month at EOD. With 10,000iu vials you will end up wasting some unless you trust that it's good for 2 months. Who really knows? I don't.
Do NOT use the (usually 1cc) amp of water/saline it comes with, just throw that away. That is intended for a fertility treatment for women, who will use the whole 5,000iu in one dose. We need a lot less than that so we reconstitute a weakened solution and refrigerate it.
Get yourself some sterile, empty vials (10cc or 30cc are fine) and some sterile, bacteriostatic water (10cc or 30cc) for injection. You can buy both at mountainsidemedical.com for quite cheap. You may as well get the 10cc vials of both since you'll save a little money. I personally don't recommend re-using the bac water...I just draw what I need from a fresh vial each time and throw the rest away. I'm not sure about sterility or shelf life once they're opened, so I trash them. They're about $1 apiece so it's a no-brainer.
Pop the flip-tops and swab all 3 stoppers with alcohol pads. With a 3cc (or larger) syringe and whatever needle you have handy (it's not thick like oil-based T, you don't need a big cannon), draw up 1cc of the bac water. Inject this into the HCG powder vial. Do NOT shake, just gently swirl if you need to--it should mix with no problem and leave you with a clear liquid.
Draw this entire solution out of the vial and inject it into your empty vial. You now have 5,000iu/1cc HCG.
You can reconstitute it at different strengths and you'd need to do the math accordingly...I personally recon at 1,000iu/cc because it's easy to dose that way and I like smaller injection volumes (who doesn't?) That means you need to add 4cc more bac water to your medication vial, to equal 5cc total including the one you've already added.
You now have 5cc of HCG solution at 1,000iu/1cc strength. Thus, 250iu=.25cc. Insulin syringes are normally graduated in units, with 100 units being 1cc (U100 insulin.) Just make sure that's what you have--it will also state the capacity in cc's at the plunger end of the barrel. So, with 1,000iu/cc HCG, all we do is lop off a zero...real simple. An indicated 25 units on the syringe (e.g., .25cc) is 250 units of HCG. Foolproof.
I like to put a label on the vial with the medication, strength, and expiration date (HCG, 1,000iu/cc, 5/5/11). Not that it's hard to remember, but why not? If you have other vials in your house it's definitely a good idea.
If you need sub-Q injection advice, just look up diabetic info, it's the same principle.
Try to get your HCG vial back in the fridge as soon as possible each time you draw up.
Hope this helps!