Stupid Question re: bathtub

ktrumpatori

So, Emma still uses her infant tub at bathtime.  She can sit up perfectly fine all by herself, etc etc.  Problem is, she's starting to get squirmy in the tub.  She's constantly throwing her toys over the side of the infant tub (into the bathtub), constantly trying to climb out, etc.  Is it time to transition her to the "big girl tub?"  If so, any suggestions on how to do this safely?  Anything I need?