While playing as Nanako, use Deploy Bits to get +7 in a single stat.
Although simple in concept, this achievement can take a long time to trigger, as bits are not prone to all allocate to the same stat. Consequently, it can be rather difficult to get a +7 stat even with Nanako's built-in +2 DEF and +1 EVD. As long as the player keeps using Nanako's Deploy Bits, they will eventually get +7 or more in one stat. It's also worth trying to use the hyper in combination with event cards that boost stat like Super All-Out Mode, to slightly increase the player's chance in favor of getting +7 attack. Putting the Amplify event could also increase the chances if you get plus one attack when active.
Another plausible way to complete this achievement is by using Nanako in co-op mode. Co-op roles have built-in stat buffs that count toward the total. For example, if the player uses Nanako as a Guardian, the player will gain an additional +2 DEF from the role at norma level 4, giving Nanako a total of +4 DEF. Then the player will only need 3 more points into defense from Deploy Bits to get the achievement. Or to make it even easier, a Fernet ally can use Air Support to add an addition +2 DEF in the player's next battle. This will provide the player with a massive +6 defense, which will make the player only need 1 more DEF point from Deploy Bits to reach 7 and trigger the achievement.