1. Time your power ups right
You're limited on power ups and using them at the right time makes the most sense. That means don't use a speed boost right before you're going to go around a corner. The odds of you slamming into a wall and wasting it are high. Instead, use it in a wide open space. Also look for cues on power ups like bubbles that elevate you. If you see a stream of coins in the air, that's probably a good time to use it.
2. Drive on the inside of the track whenever
Obviously the best route is always the shortest ones. Taking tight turns and staying on the inside of the track can shave off distance and overall time. Obviously if there's a gem on the outside of the track and you have enough of a lead or enough time to pick it up, by all means do so. But if you're racing against the clock or having a hard time passing an opponent, staying on the inside helps you gain some ground.
3. Don't waste gems on skipping challenges
Unless you absolutely can't beat a specific challenge, don't waste your gems on skipping it. Typically it costs you at least 10 gems and it's just not worth it. Try a few more times or put the game down and come back to it later. Gems are super hard to come by so use them sparingly and only when you have to.
4. Use Facebook for double rewards
Signing into your Facebook account gives you double rewards in Angry Birds Go! so if you've got a Facebook account, make sure you sign into it. Who doesn't want to earn rewards faster?
5. Angry Birds Go! codes
There are lots of special codes from sponsors you can redeem through Angry Birds Go! that you'll just have to keep your eyes peeled for. The Jenga code reveals a special pirate themed mini game. If you have the Jenga set, just enter the code. If not, you can buy the level for $1.99. Other sponsors such as State Farm run promos and have codes from time to time as well. Just keep your eyes open.