You start by moving the knight's pawn on either side to b3 or g3. Then you do the same on the other side. Ideally, you fianchetto the bishops into both triangle pawn formations.
[FEN ""] 1. b3 null 2. g3 null 3. Bb2 null 4. Bg2
I tried to use it as Black, but I am still struggling to make it into a strong defense, as it appears to be rather a powerful offensive opening. This opening seems to be gaining popularity at least for White, but I struggle to find information about it on the Internet.