I have a lot of pothos ivy in my entry--needs very little care. bigger pot will give bigger leaves. (I had mine mistaken for kudzu a few years ago!) Looks to me like you are watering it too much, and it needs to be buried deeper, not shallower. Trim at will, but probably not more than 2/3 of a single stalk at one time. You can easily root the cuttings. It does best with indirect light, but needs lots of it.