To get this achievement, you must have 100,000 dollars on you. Do not spend your money in the store, or your progress will go down.
An easy way is winning the 9-pool tour on Hard difficulty, with novice aim. By the end you would have 97,020 dollars. Just play the bonus matches for the 2,980 remaining. This will get you this achievement, plus beating 9-ball tour, and 9-ball tour on hard achievements. After getting the achievement, spend it all, earning you the Hey Big Spender achievement.
Note: Use the replay glitch while playing the tour to speed things up.