Next you roll the 20-sided die to decide your requirements.

And then…

If you rolled a 1, you choose from category 1.

If you rolled a 2, you choose from category 2.

If you rolled a 3, you choose from category 3.

If you rolled a 4, you choose from categories 1 AND 3

If you rolled a 2, you choose from categories 2 AND 3

If you rolled a 3, you choose from categories 1, 2, AND 3.