"If you do not have Java already installed, Mac OS X will promt you to download it."
"prompt" is typoed.
Also, to be pedantic, if the rest of the sentences end in punctuation, then these two should as well:
"Once the DMG installer has finished downloading, double click it to start the installation
Within the insallation window, simply drag the TripleA.app icon to the Applications folder"
"installation" is also typoed in the second sentence.