In Lotus Blossom you need to collect enough Lotus chips to reach the next milestone and collect reward. Lotuses can be found in all buildings and events, except Star Gate.  After you complete all milestones, the final reward becomes accessible. 

In Element Burst you need to blast boosters to earn points and claim rewards. Make enough blasts to reach the next milestone and collect reward. After you complete all milestones, you will get the final reward. 

Each blast adds 3 points to your progress. All blasts are counted, both triggered by your move and chip avalanches. Blasts that happen during the final blast are counted too. 

When you trigger multiple explosions in one move, the game will show your total points after all boosters have exploded. For example, if you activate one booster and it sets off two more explosions, you'll earn 9 points.

You should reach XP level 11 to participate in these events. If you’re above level 11 and the event hasn’t started for you, you may be playing an older version of the game. Please update to the most recent version through your device's app store. 

The News tab in Settings shows all upcoming events.