The following steps explain how to earn more rewards if you plan to complete clan games in clan with lower level clan perks. This trick still works as of the 28th Clan games.

Here is how the clan games rewards distributing resources. The resources rewards on each tier are base on specific percentage on each tier. It varies for each clan games. The actual rewards are calculated base as a percentage of treasury storage. Below are rewards distribution for 12th Clan Games extracted from clashofclans.wikia.com

12th Clan Games

 

Treasury storages are determine by town hall level and clan perks level. If your clan are level 1, your treasury storage are shown on this table.

  

Level 1 Clan Treasury Storage

 

This table showed the dark elixir capacity of treasury on each town hall and clan level. A town hall 9 at clan perks level five, your dark elixir treasury storage would be ninety six hundred.

Tier 4 dark elixir rewards allocation

 

In the 12th clan games, Level 5 clan and town hall 9 should be getting 3840 (40% x 9600) dark elixir at tier 4.  Below are steps that show you how to get the maximum rewards of 4800.

 

Step 1

- Assuming your existing clan level are level 9 or below.
- At the start of each clan games, before you click on Caravan for the first time, you should join higher level clans.

e.g. You are at Town Hall 9 and you intend to begin your clan games in your level 5 clan. You should join a level 10 or higher clan where it has the maximum extra treasury storage of 50%. Town hall 9 has dark elixir treasury storage of 12000. (8000 x 150%)

 

Step 2 

- After joining higher level clan, be sure you restart the game to get immediate update of your treasury storage.

e.g. Town hall 9 at level 12 clan gets 12000 dark elixir treasury storage.

 

 

Step 3

- After restart, click on Caravan and go to the rewards tab immediately. The rewards allocation will base on your town hall level and the clans level that you joinned.

e.g. Town hall 9 at level 12 clan gets 4800 dark elixir as tier 4 rewards.

 

Step 4

- Now, leave this higher level clans and return to your lower level clans.

- Your rewards allocations remain to match those of level 12 clans. Now you may start and complete any challenge.

 

At the end of clan games, you can claim your clan games rewards base on level 12 clans. You don’t need to join a higher level clans to claim the rewards. As of the 12th clan games, the rewards allocation are lock down base on the first time you click on the caravan after the start of each game.

I will post some quick reference guide on completing challenges here very soon.

 

Here are the video that walk through the steps, narrated in English