We have a clever little Pokemon trick in Pokemon X and Y that lets you use two O-Powers at once, at the cost of six orbs.
O-Powers are a new ability that you can avail in battle. Many O-Powers will increase your stats for the battle, and others will help you gain more experience or increase the chances you capture a Pokemon. You can share O-Powers with friends over the internet. O-Powers also have a regeneration period, indicated in terms of orbs. There is a maximum of ten orbs. To regenerate the orbs, you simply have to wait a few minutes. However, you can speed up this process if your 3DS logs down the amount of time you have walked with it all day. Alternately, you can shake up the 3DS to simulate the effect (which is silly, but if you need it, it works.)
The trick is actually quite simple. In battle, you use the first level 3 O-Power, and then put the 3DS on sleep mode. For the 3DS and 3DS XL, this means closing the lid, while for the 2DS this means toggling the sleep switch. While in sleep mode, the O-Power timer stops counting down. However, the orbs will continue to fill up. So, you just need to wait a few minutes, get out of sleep mode and use the second power.
This trick will be especially useful in the restaurant Le Wow. Use it there, in conjunction with the information found in our previous guide, to grind for experience and money.
Source: Reddit