I.G.
Here are a few strategies that have worked for myself or my sister:
- while you are nursing you baby on one side pump the other. I was never able to do this very successfully, but my baby was already 6 months old when I started pumping for real and she played with the pump too much. My sister had great success doing this though.
- I always got the most if I pumped in the morning, right after the first feeding.
- just randomly pump when you expect her to sleep for a longer stretch. You might not get a lot, but you will stimulate your supply. The same goes for pumping right after she finishes feeding.
Most babies will through a growths spurt around 4 weeks, during which they might nurse almost nonstop to upregulate your supply. Don't be too hard on yourself if you can't pump much during that time, it will pass after a day or a few.
And yes, you can just add small amounts to what's already frozen, you may want to cool it down in the fridge first though, to prevent thawing what's already solid. I usually collected small amounts in the fridge until I had 2 or three ounces (my daughter never ate more than that in one setting by bottle) and then popped it in the freezer.
Good luck!