I would use Bacteriostatic water, not plain sodium chloride.
Add 1 ml BW to your HCG and gently swirl if needed.
Draw your dose with a 1cc insulin or tuberculin syringe for accuracy.
Draw back to halfway to the .1 increment for 250 iu.
I generally inject 250iu 2x/week.
Store in a cool environment. If a refrigerator isn’t an option, maybe you have a cool place elsewhere.