Frequency: Frequency refers to how often something happens over time or space; in this case it's how often wave crests pass by per second - higher frequency means more waves passing by which corresponds to bluer color.
Amplitude: Amplitude refers to how 'big' or 'intense' something is; for waves it's measured from rest position up to crest - bigger amplitude means brighter light.
Phase: Phase refers to the position of a point in time on a waveform cycle. It's like tracking where you are on a roller coaster ride - at the top, bottom or somewhere in between.