First, I cut a bunch of lily pads out of crafting foam.
Then, I hot-glued a word (written on white foam) onto each lily pad.
I used words that could be formed into several easy sentences in hopes that the game will grow with him. The way we play right now is only putting five words out and then he has to hop from lily pad to lily pad reading the words. Eventually we'll work our way up to me telling him a word and he has to find it. Then, hopefully telling him a sentence and he has to hop from word to word until he's completed the sentence.