Tip 1: Collect as many studs as you can, then purchase one of the multiplier bricks as soon as possible. This will help you unlock characters much faster.

Tip 2: Smash everything, even things that don't look like they can be smashed. Sometimes the solution is right in front of you.

Tip 3: Sometimes you'll encounter things in a level that can't be interacted with until you've unlocked a character and revisit later on.