Some behaviors - as with throwing toys and pouring out milk - are normal and will pass. In the meantime, you can do things such as notice when milk is still in the cup and point out, with a silly voice, that you are pouring the milk into the cup because milk likes to be inside of things. Just occasionally, not constantly. Then just remind her when it gets on the floor, and tell her the negative consequences (as is age appropriate). You can have her play with play-doh in a safer space and with more oversight - showing her how to be neat about it while you two play.
