When online with one or more players, go to "Tour Challenges" and start a band challenge that requires two or more people. If the online player quits while selecting the difficulty, you can still do the challenge by yourself.
Easy singing
While playing any game mode as the singer, on certain songs that do not require any pitches and it is just a single pitch, you do not have to sing at all. The singer will do all the singing on their own without you having to sing yourself. You can sit back and relax, and get 100% each time.
Golden instrument icons
Play the Endless Setlist 2 under the Hard difficulty setting.
Hands-Off Moneymaking Exploit
This is a somewhat thickheaded hands-off solution to making money, but you can win songs by exploiting the "spoken word" songs and your volume settings.
First, go to the audio set up menu and turn down the volume for everything except vocals. Turn down the mic volume on the controller
Make a Playlist in a city with a few songs. Choose only the songs 'Sabotage' and 'So Whatcha Want' by the Beastie Boys, 'Give It Away' by the Red Hot Chili Peppers, and 'Testify' by Rage Against the Machine.
Start the set and leave the microphone fairly close to the speakers on your TV or audio setup Start the playlist. Because these songs are all spoken word, the game will pick up the song and nail every note, giving you almost 100 % on each song. This is a great way to rack up money. Whatever works, right?
Instruments
Complete the indicated task to unlock the corresponding instrument in the "My Closet" menu in the Rock Shop.
Bomb bass: Complete the Impossible Bass Challenge.
Bone microphone: Complete the Impossible Marathon 2 Challenge.
Clear Fender American Vintage 1962 Precision Bass: Complete the Rolling Stone Rock Immortals list on Bass.
Clear Fender American Deluxe Stratocaster HSS: Join the Rolling Stone Rock Immortals list.
Clear microphone: Complete the Rock Immortal Setlist in World Tour mode on the microphone.
Glowing drum set: Join the Rolling Stone Rock Immortals list.
Goat head bass: Complete the Impossible Marathon 2 challenge on the bass.
Goat head guitar: Complete the Impossible Marathon 2 challenge on the guitar.
Gold bass: Complete the Impossible Bass Challenge.
Gold drum set: Complete the Impossible Drum Challenge.
Gold Fender American Deluxe Stratocaster HSS: Complete the Impossible Guitar Challenge.
Gold microphone: Complete the Impossible Vocal Challenge.
Silver bass: Complete the Final Band Challenge on the bass.
Silver drum set: Complete the Final Band Challenge on the drums.
Silver Fender American Deluxe Stratocaster HSS: Complete the Final Band Challenge on the guitar.
Silver microphone: Complete the Final Band Challenge on the microphone.
Outfits
Complete the indicated task to unlock the corresponding clothing in the "My Closet" menu in the Rock Shop.
Ultimate Goth outfit: Complete the Impossible Drum Challenge.
Ultimate Metal Outfit: Complete the Impossible Vocal Challenge.
Ultimate Punk Outfit: Complete the Impossible Bass Challenge.
Ultimate Rock Outfit: Complete the Impossible Guitar Challenge.
Rearview Chaps: Complete The Final Band Challenge as a male.
Worn in the USA Chaps: Complete The Final Band Challenge as a female.
Platinum instrument icons
Play the Endless Setlist 2 under the Expert difficulty setting.
Reversed color instrument icon
Play the Endless Setlist 2 under the Medium difficulty setting.
Unlocking songs quickly
Select "Tour" in "Tour Challenges" mode. Complete the five decade challenges from 1960s through the 2000s. After completing the ten songs from the challenges you will unlock all other songs.
Various Codes
Select the "Extras" option at the main menu. Select "Modify Game" option then enter one of the following codes to activate the corresponding cheat function. Note: Enabling a code will prevent the game from being saved. Additionally, you cannot use the solo buttons on the neck of the Stratocaster to enable the codes.
Awesome Detection
Press Yellow, Blue, Orange, Yellow, Blue, Orange, Yellow, Blue, Orange. If using a Wiimote, press 2, 1, Orange, 2, 1, Orange, 2, 1, Orange.
Breakneck Speed
Press Orange, Yellow, Orange, Yellow, Blue, Orange(2), Blue. If using a Wiimote, press Orange, 2, Orange, 2, 1, Orange two times, 1. This code increases the scroll speed of the instrument tracks.
New Venues
Press Red(4), Yellow(4). If using a Wiimote, press B four times, 2 four times. This code unlocks only the venues introduced with Rock Band 2.
Performance Mode
Press Blue(2), Red(2), Yellow(2), Blue(2). If using a Wiimote, press 1 two times, B two times, 2 two times, 1 two times. This code removes the track display.
Select Venue Screen
Press Blue, Orange(2), Blue, Yellow, Blue, Orange(2), Blue, Yellow. If using a Wiimote, press 1, Orange two times, 1, 2, 1, Orange two times, 1, 2. This code unlocks all venues and disables online features.
Stage Mode
Press Blue, Yellow, Red, Blue, Yellow, Red, Blue, Yellow, Red. If using a Wiimote, press 1, 2, B, 1, 2, B, 1, 2, B. This code tweaks the game for live, public performances. It disables pausing the game, failing songs, saving the game, and online features.
Unlock All Songs
Press Red, Yellow, Blue, Red(2), Blue(2), Red, Yellow, Blue. If using a Wiimote, press B, 2, 1, B two times, 1 two times, B, 2, 1. This code disables saving the game and online features.
Video Shoot menu
Turn on the "Select Venue Screen" option. Go to the "New Venues Only" option at the "Modify Game" menu. Start the game in Quickplay mode and choose a song. A "Video Shoot" option will sometimes appears at the top of the "Select Venue" menu. Press Up to display it. These options will be "Indie Genius Video Shoot", "High-Budget Video Shoot" or "Film Student Video Shoot". Select one of them to play with the corresponding alternate background.