An announcement from Supercell stated that “Clash of Clans is about to turn three years old!”, and as a result of this, Supercell has blessed us with a one week gem boost. This announcement was also made on the 31st of July, on Clash of Clans official twitter page found here, just in case you wanted to receive updates on what Supercell is planning. This boost can be used towards all combat and resource collecting buildings (collectors, spell factories, and barracks) and allows you to maximize the effectiveness of each of them.
Now some of you might be wondering why or how a 1 gem boost can help so much and why everyone is going crazy over it. A one gem boost allows you to boost a resource collector, barrack, or spell factory by 2x all for the cost of just a single gem (per building). This gives you an extreme advantage seeing as you can have a farming army ready at twice the speed, increasing your attacker per hour and in turn increasing your resources per hour. This can also be extremely helpful when farming because so many players will have their collectors boosted, so they will have more resources collected in a shorter amount of time, so more money that you farm!
To maximize the effectiveness of this one gem boost
In this section i will be telling you how to maximize the effectiveness of this one gem boost. Now to do this trick, your collectors can NOT be maxed out. In other words, your Gold/Elixer collectors can not be level 12.
On the last day of the one gem boost, you will want to start an upgrade on these collectors. This will in turn cancel out the boost on the collectors immidiately. After you have done this, you want to cancel the upgrade, (yes you will only get 50% of what you spent on the upgrade back, but you will make up for it in the long run seeing as your collectors will be boosted for a longer period of time). After you cancel the upgrade just boost all of your collectors again and there you go, you have one more week of boosted collectors, whereas other players boosts will be coming to an end!