Masks Matter
You can get more out of each run by equipping the right mask. Some are especially useful, such as the Dog mask. It lets you gather more coins, which in time makes the game easier all around, and you also won't encounter any of those pesky snakes. Each time you can claim a new mask, check it to see what bonuses it offers. There's bound to be a mask that you'll learn to love.
Revive Wisely
You should never spend virtual currency to revive in this game, because you have a better option: just watch an ad. Then you can keep going and save your coins for something more important. Also, don't bother reviving at all unless you have a shot at continuing on to an amazing score, since there's a limit to the number of times you can revive within a given period.
Shields Are Precious
You can spin the Wheel of Fortune to earn shields, but elsewhere, they'll cost you a lot of money. Get good at working the wheel so it gives you what you want (at a cost of 200 coins per spin), but otherwise you'll want to spend coins investing in power-ups like Coin Addict and Magnet. Level those up a lot to make it easier to get additional shields, and once you have them, make sure that you're only using them when they can do the most good. If you spend them early in a run, there's no going back even if that run quickly goes sour.