(Disclaimer: this game is very buggy and achievements will not always unlock when conditions are met. Keep retrying or delete your save file and try again until they do.)
Achievements in this game are unlocked by dialing a phone number to dial into a particular site and then hacking it. You have to make sure you have open processes in order to hack, so follow these steps:
1. List Processes
2. Kill Processes 1-4
3. Dial Number. The number for the game store is 311-399-0201
4. At the Attorney Log-on screen, type CRACK
5. You now have two options; Brute Force or Ciphertext Attack. I always do Brute Force, it takes much longer but is guaranteed to work
6. Assign your four open threads to begin cracking
7. Enjoy the trippy cracking screens until the hack is complete and the achievement unlocks