Purchase attributes by maxing them out one at a time. The more you upgrade a specific attribute, the fewer ducks you need to eliminate to trigger it. Start with attributes that give you extra points, such as the Yellow Duck boost then the White Duck boost.
Scoring
The more ducks you remove from a level, the bigger the score. Try to create large lines of ducks. If you have the chance to remove two or three ducks to get more ducks for your next move, do so. Sometimes, removing the ducks one color at a time works well. Start with whatever color has the fewest ducks. Removing one color at a time may build large stacks of other colors. Spend time to prepare your moves. Search for patterns and areas where you can create large stacks of ducks.