All cheats have to be entered in the cheats menu. They do not work in Career Mode. Remember to also strum with every note/chord you hit! You should see a confirmation if you entered the code correctly. Decent pace of speed is required.

Never Fail:
Green & Red, Blue, Green & Red, Green & Yellow, Blue, Green & Yellow, Red & Yellow, Orange, Red & Yellow, Green & Yellow, Yellow, Green & Yellow, Green & Red.

Hyperspeed:
Orange, Blue, Orange, Yellow, Orange, Blue, Orange, Yellow.

Boss Characters
Once you beat a boss, he becomes unlocked.

Air Guitar
Blue & Yellow, Green & Yellow x2, Red & Blue x2, Red & Yellow x2, Blue & Yellow, Green & Yellow x2, Red & Blue x2, Red & Yellow x2, Green & Yellow x2, Red & Yellow x2.

"Through the Fire and Flames"
Complete the career mode in order to unlock the secret song

Performance Mode
Red & Yellow, Red & Blue, Red & Orange, Red & Blue, Red & Yellow, Green & Blue, Red & Yellow, Red & Blue.

Precision Mode
Green & Red x3, Red & Yellow x2, Red & Blue x2, Yellow & Blue, Yellow & Orange, Yellow & Orange, Green & Red x3, Red & Yellow x2, Red & Blue x2, Yellow & Blue, Yellow & Orange x2.

All Songs (For Quick Play and Training)
Yellow & Orange, Red & Blue, Red & Orange, Green & Blue, Red & Yellow, Yellow & Orange, Red & Yellow, Red & Blue, Green & Yellow x2, Yellow & Blue x2, Yellow & Orange x2, Yellow & Blue, Yellow, Red, Red & Yellow, Red, Yellow, Orange.

Bret Michaels, frontman of Poison
Green & Red x3, Green & Blue x4, Red & Blue, Red x3, Red & Blue, Red x3, Red & Blue, Red x3. The default singer will be replaced with Bret.