What you are training
The first image that comes to mind is the one everyone reaches for, which is why it feels like a cliche. Word association is the craft version of daydreaming: start from a seed, chain through associations, and keep going past the obvious until a word arrives that is both surprising and true to the seed. That is where fresh lyric images live, and it is the raw material of metaphor. This drill gives you a seed word and a timer and asks for a chain of associations, then asks you to circle the ones that would work in a lyric. The reveal shows how far along the chain your best words sat, which is almost never in the first three. A few rounds teach the patience to keep writing past the easy answer, and they hand you a pocketful of images to use today.
After this drill, the plan: The daily plan follows this with the metaphor builder, where the chain becomes a working comparison inside a line.